My proposal for Ant2 - Mutant

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@269017 13f79535-47bb-0310-9956-ffa450edef68

proposal/mutant/build.xml

@@ -0,0 +1,83 @@
+<project default="jars">
+    <property name="src.dir" value="src/main"/>
+    <property name="component.src.dir" value="${src.dir}/org/apache/ant/component"/>
+    <property name="build.dir" value="build"/>
+    <property name="build.classes" value="build/classes"/>
+    <property name="component.classes.dir" value="org/apache/ant/component"/>
+    <property name="build.javadocs" value="build/javadocs"/>
+    <property name="build.lib" value="${build.dir}/lib"/>
+    <property name="frontend.manifest" value="${src.dir}/org/apache/ant/frontend/manifest.mf"/>
+    <property name="egg.manifest" value="${src.dir}/org/apache/ant/frontend/eggmanifest.mf"/>
+    
+    <target name="compile">
+        <mkdir dir="${build.classes}"/>
+        <depend srcdir="${src.dir}"
+                destdir="${build.classes}"/>
+        <javac srcdir="${src.dir}"
+               destdir="${build.classes}"
+               deprecation="true"
+               debug="true"/>
+    </target>
+
+    <target name="build-task">
+        <echo message="building Task jar from ${component.classes.dir}/${taskset}/**/*.class"/>
+        <jar jarfile="${build.lib}/task/${taskset}.tsk" 
+             basedir="${build.classes}">
+            <zipfileset dir="${component.src.dir}/${taskset}" 
+                        prefix="ANT-INF" 
+                        includes="antlib.xml"/>
+            <include name="${component.classes.dir}/${taskset}/**/*.class" />
+        </jar>
+    </target>
+
+    
+    <target name="jars" depends="compile">
+        <mkdir dir="${build.lib}"/>
+        <mkdir dir="${build.lib}/task"/>
+        <jar jarfile="${build.lib}/frontend.jar" 
+             basedir="${build.classes}"
+             manifest="${frontend.manifest}">
+            <include name="org/apache/ant/frontend/*.class" />
+        </jar>
+        <jar jarfile="${build.lib}/egg.jar" 
+             basedir="${build.classes}"
+             manifest="${egg.manifest}">
+            <include name="org/apache/ant/frontend/RemoteLauncher.class" />
+            <include name="org/apache/ant/core/support/AntClassLoader.class" />
+        </jar>
+        <jar jarfile="${build.lib}/core.jar" 
+             basedir="${build.classes}">
+            <include name="org/apache/ant/core/**/*.class" />
+        </jar>
+        <antcall target="build-task">
+            <param name="taskset" value="core"/>
+        </antcall>
+        <antcall target="build-task">
+            <param name="taskset" value="file"/>
+        </antcall>
+        <copy todir="${build.lib}">
+          <fileset dir="lib"/>
+        </copy>
+    </target>
+    
+    <target name="clean">
+        <delete dir="${build.dir}"/>
+    </target>
+    
+    <target name="javadoc">
+        <mkdir dir="${build.javadocs}"/>
+        <javadoc packagenames="org.apache.*"
+                 sourcepath="${src.dir}"
+                 destdir="${build.javadocs}"
+                 author="true"
+                 version="true"
+                 windowtitle="Ant 2.0 API"
+                 doctitle="Ant 2.0"
+                 private="true"
+                 bottom="Copyright &#169; 2001 Apache Software Foundation. All Rights Reserved.">
+          <group title="Ant Core" packages="org.apache.ant.core*" />
+          <group title="Front End" packages="org.apache.ant.frontend*" />
+          <group title="XML Parsing" packages="org.apache.ant.xml*" />
+        </javadoc>
+    </target>
+</project>

proposal/mutant/src/bootstrap/org/apache/ant/bootstrap/BootstrapLoader.java

@@ -0,0 +1,298 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.bootstrap;
+
+import java.io.*;
+import java.util.*;
+import java.util.zip.*;
+import java.lang.reflect.*;
+
+/**
+ * Bootstrap class to build the rest of ant with a minimum of user intervention
+ *
+ * The bootstrap class is able to act as a class loader to load new classes/jars
+ * into the VM in which it is running.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class BootstrapLoader extends ClassLoader {
+    static public final String RECURSION_GUARD = "ant.bootstrap.recursionGuard";
+    static private final int BUFFER_SIZE = 1024;
+    
+    private String[] classpathElements;
+    
+    public BootstrapLoader(String classpath) {
+        StringTokenizer tokenizer = new StringTokenizer(classpath, File.pathSeparator);
+        classpathElements = new String[tokenizer.countTokens()];
+        
+        for (int i = 0; tokenizer.hasMoreTokens(); ++i) {
+            classpathElements[i] = tokenizer.nextToken();
+        }
+    }
+    
+    protected Class findClass(String name)
+                   throws ClassNotFoundException {
+        String resourceName = name.replace('.', '/') + ".class";
+        InputStream classStream = getResourceStream(resourceName);
+        
+        if (classStream == null) {
+            throw new ClassNotFoundException();
+        }
+        
+        try {            
+            return getClassFromStream(classStream, name);
+        }
+        catch (IOException ioe) {
+            ioe.printStackTrace();
+            throw new ClassNotFoundException();
+        }
+    }
+
+    /**
+     * Get a stream to read the requested resource name.
+     *
+     * @param name the name of the resource for which a stream is required.
+     *
+     * @return a stream to the required resource or null if the resource cannot be
+     * found on the loader's classpath.
+     */
+    private InputStream getResourceStream(String name) {
+        // we need to search the components of the path to see if we can find the 
+        // class we want. 
+        InputStream stream = null;
+ 
+        for (int i = 0; i < classpathElements.length && stream == null; ++i) {
+            File pathComponent = new File(classpathElements[i]);
+            stream = getResourceStream(pathComponent, name);
+        }
+
+        return stream;
+    }
+    
+
+                   
+    /**
+     * Get a stream to read the requested resource name.
+     *
+     * @param name the name of the resource for which a stream is required.
+     *
+     * @return a stream to the required resource or null if the resource cannot be
+     * found on the loader's classpath.
+     */
+    public InputStream getResourceAsStream(String name) {
+        return getResourceStream(name);
+    }
+    
+    protected Class loadClass(String name,
+                              boolean resolve)
+                   throws ClassNotFoundException {
+        Class requestedClass = findLoadedClass(name);
+        try {
+            if (requestedClass == null) {
+                requestedClass = findClass(name);
+                if (resolve) {
+                    resolveClass(requestedClass);
+                }
+            }
+            return requestedClass;
+        }
+        catch (ClassNotFoundException cnfe) {
+            return super.loadClass(name, resolve);
+        }
+    }                    
+
+    /**
+     * Get an inputstream to a given resource in the given file which may
+     * either be a directory or a zip file.
+     *
+     * @param file the file (directory or jar) in which to search for the resource.
+     * @param resourceName the name of the resource for which a stream is required.
+     *
+     * @return a stream to the required resource or null if the resource cannot be
+     * found in the given file object
+     */
+    private InputStream getResourceStream(File file, String resourceName) {
+        try {
+            if (!file.exists()) {
+                return null;
+            }
+            
+            if (file.isDirectory()) {
+                File resource = new File(file, resourceName); 
+                
+                if (resource.exists()) {   
+                    return new FileInputStream(resource);
+                }
+            }
+            else {
+                ZipFile zipFile = null;
+                try {
+                    zipFile = new ZipFile(file);
+        
+                    ZipEntry entry = zipFile.getEntry(resourceName);
+                    if (entry != null) {
+                        // we need to read the entry out of the zip file into
+                        // a baos and then 
+                        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                        byte[] buffer = new byte[BUFFER_SIZE];
+                        int bytesRead;
+                        InputStream stream = zipFile.getInputStream(entry);
+                        while ((bytesRead = stream.read(buffer, 0, BUFFER_SIZE)) != -1) {
+                            baos.write(buffer, 0, bytesRead);
+                        }
+                        return new ByteArrayInputStream(baos.toByteArray());   
+                    }
+                }
+                finally {
+                    if (zipFile != null) {
+                        zipFile.close();
+                    }
+                }
+            }
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+        
+        return null;   
+    }
+
+    /**
+     * Read a class definition from a stream.
+     *
+     * @param stream the stream from which the class is to be read.
+     * @param classname the class name of the class in the stream.
+     *
+     * @return the Class object read from the stream.
+     *
+     * @throws IOException if there is a problem reading the class from the
+     * stream.
+     */
+    private Class getClassFromStream(InputStream stream, String classname) 
+                throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        int bytesRead = -1;
+        byte[] buffer = new byte[1024];
+        
+        while ((bytesRead = stream.read(buffer, 0, 1024)) != -1) {
+            baos.write(buffer, 0, bytesRead);
+        }
+        
+        byte[] classData = baos.toByteArray();
+
+        return defineClass(classname, classData, 0, classData.length); 
+    }
+
+
+    static private void buildAnt() {
+        System.out.println("Bootstrapping Ant ...");
+        
+    }
+
+    static private void runWithToolsJar(String[] args) {
+        try {
+            
+            String javaHome = System.getProperty("java.home");
+            if (javaHome.endsWith("jre")) {
+                javaHome = javaHome.substring(0, javaHome.length() - 4);
+            }
+            File toolsjar = new File(javaHome + "/lib/tools.jar");
+            if (!toolsjar.exists()) {
+                System.out.println("Unable to locate tools.jar. expected it to be in " +
+                                           toolsjar.getPath());
+                return;                                           
+            }                                            
+            String newclasspath = toolsjar.getPath() + File.pathSeparator + 
+                                  System.getProperty("java.class.path");
+            
+            System.out.println("New Classpath is " + newclasspath);
+            
+            BootstrapLoader loader = new BootstrapLoader(newclasspath);
+            
+            Class newBootClass = loader.loadClass("org.apache.ant.bootstrap.BootstrapLoader",
+                                                  true);
+            final Class[] param = { Class.forName("[Ljava.lang.String;") };
+            final Method main = newBootClass.getMethod("main", param);
+            final Object[] argument = { args };
+            main.invoke(null, argument);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+            throw new RuntimeException("Unable to run boot with tools.jar");
+        }
+    }
+    
+    static public void main(String[] args) {
+        // check whether the tools.jar is already in the classpath.
+        try {
+            Class compilerClass = Class.forName("sun.tools.javac.Main");
+            System.out.println("Compiler is available");
+        } catch (ClassNotFoundException cnfe) {
+            if (System.getProperty(RECURSION_GUARD) != null) {
+                cnfe.printStackTrace();
+                System.out.println("Unable to load compiler");
+                return;
+            }
+            System.setProperty(RECURSION_GUARD, "yes");
+            System.out.println("Compiler is not on classpath - locating ...");
+            runWithToolsJar(args);
+            return;                                                           
+        }
+        
+        buildAnt();
+    }
+}
+
+

proposal/mutant/src/main/org/apache/ant/component/core/Echo.java

@@ -0,0 +1,162 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights 
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:  
+ *       "This product includes software developed by the 
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written 
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.component.core;
+
+import org.apache.ant.core.execution.*;
+import org.apache.ant.core.types.*;
+import java.io.*;
+
+/**
+ * Echo
+ *
+ * @author costin@dnt.ro
+ */
+public class Echo extends ExecutionTask {
+    protected String message = ""; // required
+    protected File file = null;
+    protected boolean append = false;
+    
+    // by default, messages are always displayed
+    protected int logLevel = BuildEvent.MSG_WARN;   
+    
+    /**
+     * Does the work.
+     *
+     * @throws ExecutionException if someting goes wrong with the build
+     */
+    public void execute() throws ExecutionException {
+        if (file == null) {
+            log(message, logLevel);
+        } else {
+            FileWriter out = null;
+            try {
+                out = new FileWriter(file.getAbsolutePath(), append);
+                out.write(message, 0, message.length());
+            } catch (IOException ioe) {
+                throw new ExecutionException(ioe);
+            } finally {
+                if (out != null) {
+                    try {
+                        out.close();
+                    } catch (IOException ioex) {}
+                }
+            }
+        }
+    }
+
+    /**
+     * Sets the message variable.
+     *
+     * @param msg Sets the value for the message variable.
+     */
+    public void setMessage(String msg) {
+        this.message = msg;
+    }
+
+    /**
+     * Sets the file attribute.
+     */
+    public void setFile(File file) {
+        this.file = file;
+    }
+
+    /**
+     * Shall we append to an existing file?
+     */
+    public void setAppend(boolean append) {
+        this.append = append;
+    }
+
+    /**
+     * Set a multiline message.
+     */
+    public void addText(String msg) {
+        message += msg;
+    }
+
+    /**
+     * Set the logging level to one of
+     * <ul>
+     *  <li>error</li>
+     *  <li>warning</li>
+     *  <li>info</li>
+     *  <li>verbose</li>
+     *  <li>debug</li>
+     * <ul>
+     * <p>The default is &quot;warning&quot; to ensure that messages are
+     * displayed by default when using the -quiet command line option.</p>
+     */
+    public void setLevel(EchoLevel echoLevel) {
+        String option = echoLevel.getValue();
+        if (option.equals("error")) {
+            logLevel = BuildEvent.MSG_ERR;
+        } else if (option.equals("warning")) {
+            logLevel = BuildEvent.MSG_WARN;
+        } else if (option.equals("info")) {
+            logLevel = BuildEvent.MSG_INFO;
+        } else if (option.equals("verbose")) {
+            logLevel = BuildEvent.MSG_VERBOSE;
+        } else {
+            // must be "debug"
+            logLevel = BuildEvent.MSG_DEBUG;
+        }
+    }
+
+    public static class EchoLevel extends EnumeratedAttribute {
+        public String[] getValues() {
+            return new String[] {"error", "warning", "info", "verbose", "debug"};
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/component/core/EnumeratedAttributeConverter.java

@@ -0,0 +1,98 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.component.core;
+
+import org.apache.ant.core.execution.*;
+import org.apache.ant.core.types.EnumeratedAttribute;
+
+/**
+ * Convert between a string and an enumeration
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class EnumeratedAttributeConverter implements AntConverter {
+    private ExecutionFrame frame;
+    
+    public void init(ExecutionFrame frame) {
+        this.frame = frame;
+    }
+    
+    public Object convert(String value, Class type) throws ConversionException {
+        // The string represents a value
+        // get the frame's URL
+        try {
+            Object instance = type.newInstance();
+            if (!(instance instanceof EnumeratedAttribute)) {
+                throw new ConversionException("The type " + type.getName() 
+                                             + " is not a subclass of EnumeratedAttribute");
+            }
+            EnumeratedAttribute enum = (EnumeratedAttribute)instance;
+            enum.setValue(value.trim());
+            return enum;
+        }
+        catch (InstantiationException e) {
+            throw new ConversionException("Unable to instantiate the enumerated type "
+                                          + type.getName());
+        }
+        catch (IllegalAccessException e) {
+            throw new ConversionException("Illegale access when instantiation enumerated type "
+                                          + type.getName());
+        }
+        catch (ExecutionException e) {
+            throw new ConversionException("Unable to set the value of the enumerated type "
+                                          + type.getName() + ": " + e.getMessage());
+        }                                                      
+    }
+}

proposal/mutant/src/main/org/apache/ant/component/core/FileConverter.java

@@ -0,0 +1,89 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.component.core;
+
+import java.io.File;
+import java.net.*;
+import org.apache.ant.core.execution.*;
+
+/**
+ * Convert between a string and a data type
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class FileConverter implements AntConverter {
+    private ExecutionFrame frame;
+    
+    public void init(ExecutionFrame frame) {
+        this.frame = frame;
+    }
+    
+    public Object convert(String value, Class type) throws ConversionException {
+        // The string represents a value
+        // get the frame's URL
+        try {
+            URL url = new URL(frame.getBaseURL(), value);
+            if (url.getProtocol().equals("file")) {
+                System.out.println("Converted URL to " + url);
+                return new File(url.getFile());
+            }
+            return new File(value);
+        }
+        catch (MalformedURLException e) {
+            throw new ConversionException("Unable to convert " + value 
+                                          + " into a File relative to the project's base");
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/component/core/Property.java

@@ -0,0 +1,252 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.component.core;
+
+import java.util.*;
+import java.io.*;
+import org.apache.ant.core.execution.*;
+import java.net.*;
+
+/**
+ * 
+ */ 
+public class Property extends ExecutionTask {
+    private String name;
+    private String value;
+    private URL file;
+    private String resource;
+//    private Path classpath;
+    private String env;
+//    private Reference ref = null;
+    
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setValue(String value) {
+        this.value = value;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    public void setFile(URL file) {
+        this.file = file;
+    }
+
+    public URL getFile() {
+        return file;
+    }
+
+    public void setLocation(File location) {
+        setValue(location.getAbsolutePath());
+    }
+
+//    public void setRefid(Reference ref) {
+//        this.ref = ref;
+//    }
+//
+//    public Reference getRefid() {
+//        return ref;
+//    }
+//
+    public void setResource(String resource) {
+        this.resource = resource;
+    }
+
+    public String getResource() {
+        return resource;
+    }
+
+    public void setEnvironment(String env) {
+        this.env = env;
+    }
+
+    public String getEnvironment() {
+        return env;
+    }
+
+//    public void setClasspath(Path classpath) {
+//        if (this.classpath == null) {
+//            this.classpath = classpath;
+//        } else {
+//            this.classpath.append(classpath);
+//        }
+//    }
+//    
+//    public Path createClasspath() {
+//        if (this.classpath == null) {
+//            this.classpath = new Path(project);
+//        }
+//        return this.classpath.createPath();
+//    }
+//    
+//    public void setClasspathRef(Reference r) {
+//        createClasspath().setRefid(r);
+//    }
+//
+
+    public void execute() throws ExecutionException {
+        ExecutionFrame frame = getExecutionFrame();
+        if ((name != null) && (value != null)) {
+            frame.setDataValue(name, value);
+        }
+
+        if (file != null) {
+            loadFile(file);
+        }
+
+//        if (resource != null) loadResource(resource);
+//
+//        if (env != null) loadEnvironment(env);
+//
+//        if ((name != null) && (ref != null)) {
+//            Object obj = ref.getReferencedObject(getProject());
+//            if (obj != null) {
+//                addProperty(name, obj.toString());
+//            }
+//        }
+    }
+
+    protected void loadFile (URL url) throws ExecutionException {
+        Properties props = new Properties();
+        log("Loading " + url, BuildEvent.MSG_VERBOSE);
+        try {
+            InputStream stream = null;
+            if (url.getProtocol().equals("file")) {
+                File file = new File(url.getFile());
+            
+                if (file.exists()) {
+                    stream = new FileInputStream(file);
+                } 
+                else {
+                    throw new ExecutionException("Unable to find " + file.getAbsolutePath());
+                }
+            }
+            else {
+                stream = url.openStream();
+            }
+            
+            if (stream != null) {
+                try { 
+                    props.load(stream);
+                    resolveAllProperties(props);
+                    addProperties(props);
+                } finally {
+                    stream.close();
+                }
+            }
+        } catch (Exception ex) {
+            throw new ExecutionException("Unable to load property file: " + url, ex);
+        }
+    }
+
+    protected void addProperties(Properties properties) throws ExecutionException {
+        ExecutionFrame frame = getExecutionFrame();
+        for (Iterator i = properties.keySet().iterator(); i.hasNext();) {
+            String propertyName = (String)i.next();
+            String propertyValue = properties.getProperty(propertyName);
+            frame.setDataValue(propertyName, frame.replacePropertyRefs(propertyValue));
+        }
+    }
+
+    private void resolveAllProperties(Properties props) throws ExecutionException {
+        for (Iterator propIterator = props.keySet().iterator(); propIterator.hasNext();) {
+            String name = (String)propIterator.next();
+            String value = props.getProperty(name);
+
+            boolean resolved = false;
+            while (!resolved) {
+                List fragments = new ArrayList();
+                List propertyRefs = new ArrayList();
+                ExecutionFrame.parsePropertyString(value, fragments, propertyRefs);
+                
+                resolved = true;
+                if (propertyRefs.size() != 0) {
+                    StringBuffer sb = new StringBuffer();
+                    Iterator i = fragments.iterator();
+                    Iterator j = propertyRefs.iterator();
+                    while (i.hasNext()) {
+                        String fragment = (String)i.next();
+                        if (fragment == null) {
+                            String propertyName = (String)j.next();
+                            if (propertyName.equals(name)) {
+                                throw new ExecutionException("Property " + name 
+                                                             + " from " + file 
+                                                             + " was circularly defined.");
+                            }
+                            if (props.containsKey(propertyName)) {
+                                fragment = props.getProperty(propertyName);
+                                resolved = false;
+                            }
+                            else {
+                                fragment = "${" + propertyName + "}";
+                            }
+                        }
+                        sb.append(fragment);
+                    }
+                    value = sb.toString();
+                    props.put(name, value);
+                }
+            }
+        }
+    }    
+}
+

proposal/mutant/src/main/org/apache/ant/component/core/URLConverter.java

@@ -0,0 +1,86 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.component.core;
+
+import org.apache.ant.core.execution.*;
+
+import java.net.*;
+import java.io.File;
+
+/**
+ * Convert between a string and a URL, resolved to the ExecutionFrame's base
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class URLConverter implements AntConverter {
+    private ExecutionFrame frame;
+    
+    public void init(ExecutionFrame frame) {
+        this.frame = frame;
+    }
+    
+    public Object convert(String value, Class type) throws ConversionException {
+        // The string represents a value
+        // get the frame's URL
+        try {
+            URL url = new URL(frame.getBaseURL(), value);
+            return url;
+        }
+        catch (MalformedURLException e) {
+            throw new ConversionException("Unable to convert " + value 
+                                          + " into a URL relative to the project's base");
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/component/core/antlib.xml

@@ -0,0 +1,8 @@
+<antlib>
+   <taskdef name="property" classname="org.apache.ant.component.core.Property"/>
+   <taskdef name="echo" classname="org.apache.ant.component.core.Echo"/>
+   <converter target="java.io.File" classname="org.apache.ant.component.core.FileConverter"/>
+   <converter target="java.net.URL" classname="org.apache.ant.component.core.URLConverter"/>
+   <converter target="org.apache.ant.core.types.EnumeratedAttribute" 
+              classname="org.apache.ant.component.core.EnumeratedAttributeConverter"/>
+</antlib>

proposal/mutant/src/main/org/apache/ant/component/file/antlib.xml

@@ -0,0 +1,2 @@
+<antlib>
+</antlib>

proposal/mutant/src/main/org/apache/ant/core/config/ComponentManager.java

@@ -0,0 +1,147 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.config;
+
+import java.io.*;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.*;
+import org.apache.ant.core.execution.*;
+import org.apache.ant.core.support.*;
+import org.apache.ant.core.xml.AntLibParser;
+import org.xml.sax.SAXParseException;
+
+/**
+ * Manager for Ant components
+ *
+ * The component manager is responsible for locating and loading the 
+ * components contained in Ant's lib/task directory.
+ * 
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class ComponentManager {
+    /**
+     * When Ant is run remotely, we need to look up the list of component
+     * libraries from the server.
+     */
+    static public String COMPONENT_INDEX = "taskindex";
+    
+    /**
+     * Create the component manager. When the component manager is created
+     * it will read the component definitions from the  files in
+     * Ant's lib/task directory
+     */ 
+    static public AntLibrary[] getComponents() throws LocationException, ConfigException {
+        try {
+            URL componentsLocation = new URL(AntLocator.getLibraryURL(), "task/");
+            URL[] componentFiles = null;
+            if (componentsLocation.getProtocol().equals("file")) {
+                // component directory is local - we determine the 
+                // component files by scanning the local directory
+                HashSet componentFilesTypes = new HashSet();
+                componentFilesTypes.add(".tsk");
+                componentFilesTypes.add(".jar");
+                componentFilesTypes.add(".zip");
+                File componentsDirectory = new File(componentsLocation.getFile());
+                componentFiles = AntLocator.getDirectoryURLs(componentsDirectory, componentFilesTypes);
+            }
+            else {
+                // The component directory is remote - we determine the
+                // list of component files by reading a "known"  list file.
+                URL componentListURL = new URL(componentsLocation, COMPONENT_INDEX);
+                BufferedReader reader = null;
+                List componentList = new ArrayList();
+                try {
+                    reader = new BufferedReader(new InputStreamReader(componentListURL.openStream()));
+                    String line = null;
+                    while ((line = reader.readLine()) != null) {
+                        componentList.add(new URL(componentsLocation, line.trim()));
+                    }
+                }
+                finally {
+                    if (reader != null) {
+                        reader.close();
+                    }
+                }
+                componentFiles = (URL[])componentList.toArray(new URL[0]);
+            }
+                        
+            AntLibParser libdefParser = new AntLibParser();
+            
+            List libraries = new ArrayList();
+            
+            for (int i = 0; i < componentFiles.length; ++i) {
+                // We create a classloader for the component library
+                URL[] componentURLs = new URL[]{componentFiles[i]};
+                AntClassLoader componentClassLoader 
+                    = new AntClassLoader(componentURLs, 
+                                         ComponentManager.class.getClassLoader(),
+                                         componentFiles[i].toString());
+                URL libDefinition = componentClassLoader.getResource("ANT-INF/antlib.xml");
+                if (libDefinition != null) {
+                    AntLibrary library 
+                        = libdefParser.parseAntLibrary(libDefinition, componentClassLoader);
+                    libraries.add(library);                            
+                }
+            }
+            
+            return (AntLibrary[])libraries.toArray(new AntLibrary[0]);
+        }
+        catch (IOException e) {
+            throw new ConfigException(e);
+        }
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/execution/AntConverter.java

@@ -0,0 +1,65 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+/**
+ * An AntConverter is a Converter which is initialised with the 
+ * ExecutionFrame context in which it will perform its conversions
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public interface AntConverter extends Converter {
+    void init(ExecutionFrame frame);
+}

proposal/mutant/src/main/org/apache/ant/core/execution/AntLibrary.java

@@ -0,0 +1,110 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.util.*;
+import java.net.URL;
+
+/**
+ * This object represents an Ant library definition. An Ant library
+ * is a set of plug-in for Ant consisting primarily of tasks but may include
+ * other ant components.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class AntLibrary {
+    /**
+     * The task definitions contained by this library
+     */
+    private List taskDefinitions = new ArrayList();
+    
+    /**
+     * The converter definitions contained by this library
+     */
+    private List converterDefinitions = new ArrayList();
+    
+    /**
+     * Add a task definition to this library
+     */
+    public void addTaskDefinition(TaskDefinition taskDefinition) {
+        taskDefinitions.add(taskDefinition);
+    }
+   
+    /**
+     * Get the task definitions
+     *
+     * @return an iterator which returns TaskDefinition objects.
+     */
+    public Iterator getTaskDefinitions() {
+        return taskDefinitions.iterator();
+    }
+    
+    /**
+     * Add a converter definition to this library
+     */
+    public void addConverterDefinition(ConverterDefinition converterDefinition) {
+        converterDefinitions.add(converterDefinition);
+    }
+   
+    /**
+     * Get the converter definitions
+     *
+     * @return an iterator which returns ConverterDefinition objects.
+     */
+    public Iterator getConverterDefinitions() {
+        return converterDefinitions.iterator();
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/execution/BuildEvent.java

@@ -0,0 +1,171 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+import java.util.EventObject;
+import org.apache.ant.core.model.*;
+
+/*
+ * A BuildEvent indicates the occurence of a significant event
+ * in the build.
+ *
+ * All build events come from an ExecutionFrame or an ExecutionManager.
+ * There are a number of different types of event and they will
+ * generally be associated with some build element from the build model.
+ */
+public class BuildEvent extends EventObject {
+    public static final int MSG_ERR = 0;
+    public static final int MSG_WARN = 1;
+    public static final int MSG_INFO = 2;
+    public static final int MSG_VERBOSE = 3;
+    public static final int MSG_DEBUG = 4;
+
+    public static final int BUILD_STARTED = 1;
+    public static final int BUILD_FINISHED = 2;
+    public static final int TARGET_STARTED = 3;
+    public static final int TARGET_FINISHED = 4;
+    public static final int TASK_STARTED = 5;
+    public static final int TASK_FINISHED = 6;
+    public static final int MESSAGE = 7;
+
+    private int eventType;
+    private BuildElement buildElement = null;
+    private Throwable cause = null;
+    private String message = null;
+    private int messagePriority;
+
+    /**
+     * Create a build event. 
+     * 
+     * @param soure the source of the build event.
+     * @param eventType the type of the buildEvent.
+     * @param buildElement the build element with which the event is associated.
+     */
+    public BuildEvent(Object source, int eventType, BuildElement buildElement) {
+        super(source);
+        this.eventType = eventType;
+        this.buildElement = buildElement;
+    }
+    
+    /**
+     * Create a build event with an associated exception. 
+     * 
+     * @param soure the source of the build event.
+     * @param eventType the type of the buildEvent.
+     * @param buildElement the build element with which the event is associated.
+     */
+    public BuildEvent(Object source, int eventType, BuildElement buildElement, 
+                      Throwable cause) {
+        this(source, eventType, buildElement);                        
+        this.cause = cause;
+    }
+
+    /**
+     * Create a build event for a message 
+     * 
+     * @param soure the source of the build event.
+     * @param buildElement the build element with which the event is associated.
+     * @param message the message associated with this event
+     * @param priority the message priority
+     */
+    public BuildEvent(Object source, BuildElement buildElement, String message, 
+                      int priority) {
+        this(source, MESSAGE, buildElement);                        
+        this.message = message;
+        this.messagePriority = priority;
+    }
+    
+    /**
+     * Get the type of this event
+     *
+     * @return the event type
+     */
+    public int getEventType() {
+        return eventType;
+    }
+    
+    /**
+     * Get the build element involved in this event.
+     *
+     * @return the build element to which this event is associated.
+     */
+    public BuildElement getBuildElement() {
+        return buildElement;
+    }
+    
+    /**
+     *  Returns the logging message. This field will only be set
+     *  for "messageLogged" events.
+     *
+     */
+    public String getMessage() {
+        return message;
+    }
+
+    /**
+     *  Returns the priority of the logging message. This field will only
+     *  be set for "messageLogged" events.
+     */
+    public int getPriority(){
+        return messagePriority;
+    }
+
+    /**
+     *  Returns the exception that was thrown, if any. This field will only
+     *  be set for "taskFinished", "targetFinished", and "buildFinished" events.
+     */
+    public Throwable getCause() {
+        return cause;
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/BuildEventSupport.java

@@ -0,0 +1,116 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+import java.util.*;
+import org.apache.ant.core.model.*;
+
+/**
+ * BuildEventSupport is used by classes which which to send 
+ * build events to the BuoldListeners
+ */
+public class BuildEventSupport {
+    private List listeners = new ArrayList();
+    
+    public void addBuildListener(BuildListener listener) {
+        listeners.add(listener);
+    }
+    
+    public void removeBuildListener(BuildListener listener) {
+        listeners.remove(listener);
+    }
+
+    public void forwardEvent(BuildEvent event) {
+        for (Iterator i = listeners.iterator(); i.hasNext();) {
+            BuildListener listener = (BuildListener)i.next();
+            listener.processBuildEvent(event);
+        }
+    }
+    
+    public void fireBuildStarted(Object source, BuildElement element) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.BUILD_STARTED, element);
+        forwardEvent(event);
+    }
+
+    public void fireBuildFinished(Object source, BuildElement element, Throwable cause) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.BUILD_FINISHED, element, cause);
+        forwardEvent(event);
+    }
+
+    public void fireTargetStarted(Object source, BuildElement element) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.TARGET_STARTED, element);
+        forwardEvent(event);
+    }
+
+    public void fireTargetFinished(Object source, BuildElement element, Throwable cause) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.TARGET_FINISHED, element, cause);
+        forwardEvent(event);
+    }
+
+    public void fireTaskStarted(Object source, BuildElement element) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.TASK_STARTED, element);
+        forwardEvent(event);
+    }
+
+    public void fireTaskFinished(Object source, BuildElement element, Throwable cause) {
+        BuildEvent event = new BuildEvent(source, BuildEvent.TASK_FINISHED, element, cause);
+        forwardEvent(event);
+    }
+
+    public void fireMessageLogged(Object source, BuildElement element,
+                                   String message, int priority) {
+        BuildEvent event = new BuildEvent(source,  element, message, priority);
+        forwardEvent(event);
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/BuildListener.java

@@ -0,0 +1,67 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.util.EventListener;
+
+/**
+ *  Classes that implement this interface will be notified when
+ *  things happend during a build.
+ *
+ *  @see BuildEvent
+ */
+public interface BuildListener extends EventListener {
+    void processBuildEvent(BuildEvent event);
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ClassIntrospectionException.java

@@ -0,0 +1,144 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+
+import java.io.*;
+
+/**
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ClassIntrospectionException extends Exception {
+    /** 
+     * Exception that might have caused this one. 
+     */
+    private Throwable cause = null;
+
+    /**
+     * Constructs an exception with the given descriptive message.
+     * @param msg Description of or information about the exception.
+     */
+    public ClassIntrospectionException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public ClassIntrospectionException(String msg, Throwable cause) {
+        super(msg);
+        this.cause = cause;
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     * @param cause Exception that might have caused this one.
+     */
+    public ClassIntrospectionException(Throwable cause) {
+        super(cause.toString());
+        this.cause = cause;
+    }
+
+    /**
+     * Returns the nested exception.
+     *
+     * @return the underlying exception
+     */
+    public Throwable getCause() {
+        return cause;
+    }
+
+    /**
+     * Print the stack trace to System.err
+     */
+    public void printStackTrace() {
+        printStackTrace(System.err);
+    }
+    
+    /**
+     * Print the stack trace to the given PrintStream
+     *
+     * @param ps the PrintStream onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintStream ps) {
+        synchronized (ps) {
+            ps.println(this);
+            if (cause != null) {
+                ps.println("--- Nested Exception ---");
+                cause.printStackTrace(ps);
+            }
+        }
+    }
+    
+    /**
+     * Print the stack trace to the given PrintWriter
+     *
+     * @param pw the PrintWriter onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintWriter pw) {
+        synchronized (pw) {
+            pw.println(this);
+            if (cause != null) {
+                pw.println("--- Nested Exception ---");
+                cause.printStackTrace(pw);
+            }
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ClassIntrospector.java

@@ -0,0 +1,477 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.lang.reflect.*;
+import java.io.File;
+import java.util.*;
+
+/**
+ * Introspects a class and builds a set of objects to assist in intospecting the 
+ * class.
+ *
+ * @author Stefan Bodewig <a href="mailto:stefan.bodewig@megabit.net">stefan.bodewig@megabit.net</a> 
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ClassIntrospector {
+    /**
+     * holds the types of the attributes that could be set.
+     */
+    private Hashtable attributeTypes;
+
+    /**
+     * holds the attribute setter methods.
+     */
+    private Hashtable attributeSetters;
+
+    /**
+     * Holds the types of nested elements that could be created.
+     */
+    private Hashtable nestedTypes;
+
+    /**
+     * Holds methods to create nested elements.
+     */
+    private Hashtable nestedCreators;
+
+    /**
+     * The method to add PCDATA stuff.
+     */
+    private Method addText = null;
+
+    /**
+     * The Class that's been introspected.
+     */
+    private Class bean;
+
+    /**
+     * returns the boolean equivalent of a string, which is considered true
+     * if either "on", "true", or "yes" is found, ignoring case.
+     */
+    public static boolean toBoolean(String s) {
+        return (s.equalsIgnoreCase("on") ||
+                s.equalsIgnoreCase("true") ||
+                s.equalsIgnoreCase("yes"));
+    }
+
+    public ClassIntrospector(final Class bean, Map converters) {
+        attributeTypes = new Hashtable();
+        attributeSetters = new Hashtable();
+        nestedTypes = new Hashtable();
+        nestedCreators = new Hashtable();
+        this.bean = bean;
+
+        Method[] methods = bean.getMethods();
+        for (int i=0; i<methods.length; i++) {
+            final Method m = methods[i];
+            final String name = m.getName();
+            Class returnType = m.getReturnType();
+            Class[] args = m.getParameterTypes();
+
+            if ("addText".equals(name)
+                && java.lang.Void.TYPE.equals(returnType)
+                && args.length == 1
+                && java.lang.String.class.equals(args[0])) {
+
+                addText = methods[i];
+
+            } else if (name.startsWith("set")
+                       && java.lang.Void.TYPE.equals(returnType)
+                       && args.length == 1
+                       && !args[0].isArray()) {
+
+                String propName = getPropertyName(name, "set");
+                AttributeSetter as = createAttributeSetter(m, args[0], converters);
+                if (as != null) {
+                    attributeTypes.put(propName, args[0]);
+                    attributeSetters.put(propName, as);
+                }
+
+            } else if (name.startsWith("create")
+                       && !returnType.isArray()
+                       && !returnType.isPrimitive()
+                       && args.length == 0) {
+
+                String propName = getPropertyName(name, "create");
+                nestedTypes.put(propName, returnType);
+                nestedCreators.put(propName, new NestedCreator() {
+
+                        public Object create(Object parent) 
+                            throws InvocationTargetException, 
+                            IllegalAccessException {
+
+                            return m.invoke(parent, new Object[] {});
+                        }
+
+                    });
+                
+            } else if (name.startsWith("add")
+                       && java.lang.Void.TYPE.equals(returnType)
+                       && args.length == 1
+                       && !java.lang.String.class.equals(args[0])
+                       && !args[0].isArray()
+                       && !args[0].isPrimitive()) {
+                 
+                try {
+                    final Constructor c = 
+                        args[0].getConstructor(new Class[] {});
+                    String propName = getPropertyName(name, "add");
+                    nestedTypes.put(propName, args[0]);
+                    nestedCreators.put(propName, new NestedCreator() {
+
+                            public Object create(Object parent) 
+                                throws InvocationTargetException, IllegalAccessException, InstantiationException {
+                                
+                                Object o = c.newInstance(new Object[] {});
+                                m.invoke(parent, new Object[] {o});
+                                return o;
+                            }
+
+                        });
+                } catch (NoSuchMethodException nse) {
+                }
+                    
+            }
+        }
+    }
+    
+    /**
+     * Sets the named attribute.
+     */
+    public void setAttribute(Object element, String attributeName, 
+                             String value)
+        throws ClassIntrospectionException, ConversionException {
+        AttributeSetter as = (AttributeSetter) attributeSetters.get(attributeName);
+        if (as == null) {
+            String msg = "Class " + element.getClass().getName() +
+                " doesn't support the \"" + attributeName + "\" attribute";
+            throw new ClassIntrospectionException(msg);
+        }
+        try {
+            as.set(element, value);
+        } catch (IllegalAccessException ie) {
+            // impossible as getMethods should only return public methods
+            throw new ClassIntrospectionException(ie);
+        } catch (InvocationTargetException ite) {
+            Throwable t = ite.getTargetException();
+            if (t instanceof ClassIntrospectionException) {
+                throw (ClassIntrospectionException) t;
+            }
+            throw new ClassIntrospectionException(t);
+        }
+    }
+
+    /**
+     * Adds PCDATA areas.
+     */
+    public void addText(Object element, String text) 
+        throws ClassIntrospectionException {
+            
+        if (addText == null) {
+            String msg = "Class " + element.getClass().getName() +
+                " doesn't support nested text elements";
+            throw new ClassIntrospectionException(msg);
+        }
+        try {
+            addText.invoke(element, new String[] {text});
+        } catch (IllegalAccessException ie) {
+            // impossible as getMethods should only return public methods
+            throw new ClassIntrospectionException(ie);
+        } catch (InvocationTargetException ite) {
+            Throwable t = ite.getTargetException();
+            if (t instanceof ClassIntrospectionException) {
+                throw (ClassIntrospectionException) t;
+            }
+            throw new ClassIntrospectionException(t);
+        }
+    }
+
+    public boolean supportsNestedElement(String elementName) {
+        return nestedCreators.containsKey(elementName);
+    }
+
+    /**
+     * Creates a named nested element.
+     */
+    public Object createElement(Object element, String elementName) 
+         throws ClassIntrospectionException {
+        NestedCreator nc = (NestedCreator) nestedCreators.get(elementName);
+        if (nc == null) {
+            String msg = "Class " + element.getClass().getName() +
+                " doesn't support the nested \"" + elementName + "\" element";
+            throw new ClassIntrospectionException(msg);
+        }
+        try {
+            return nc.create(element);
+        } catch (IllegalAccessException ie) {
+            // impossible as getMethods should only return public methods
+            throw new ClassIntrospectionException(ie);
+        } catch (InstantiationException ine) {
+            // impossible as getMethods should only return public methods
+            throw new ClassIntrospectionException(ine);
+        } catch (InvocationTargetException ite) {
+            Throwable t = ite.getTargetException();
+            if (t instanceof ClassIntrospectionException) {
+                throw (ClassIntrospectionException) t;
+            }
+            throw new ClassIntrospectionException(t);
+        }
+    }
+
+    /**
+     * returns the type of a named nested element.
+     */
+    public Class getElementType(String elementName) 
+        throws ClassIntrospectionException  {
+        Class nt = (Class) nestedTypes.get(elementName);
+        if (nt == null) {
+            String msg = "Class " + bean.getName() +
+                " doesn't support the nested \"" + elementName + "\" element";
+            throw new ClassIntrospectionException(msg);
+        }
+        return nt;
+    }
+
+    /**
+     * returns the type of a named attribute.
+     */
+    public Class getAttributeType(String attributeName) 
+        throws ClassIntrospectionException {
+        Class at = (Class) attributeTypes.get(attributeName);
+        if (at == null) {
+            String msg = "Class " + bean.getName() +
+                " doesn't support the \"" + attributeName + "\" attribute";
+            throw new ClassIntrospectionException(msg);
+        }
+        return at;
+    }
+
+    /**
+     * Does the introspected class support PCDATA?
+     */
+    public boolean supportsCharacters() {
+        return addText != null;
+    }
+
+    /**
+     * Return all attribues supported by the introspected class.
+     */
+    public Enumeration getAttributes() {
+        return attributeSetters.keys();
+    }
+
+    /**
+     * Return all nested elements supported by the introspected class.
+     */
+    public Enumeration getNestedElements() {
+        return nestedTypes.keys();
+    }
+
+    /**
+     * Create a proper implementation of AttributeSetter for the given
+     * attribute type.  
+     */
+    private AttributeSetter createAttributeSetter(final Method m,
+                                                  final Class arg,
+                                                  Map converters) {
+
+        if (converters != null && converters.containsKey(arg)) {
+            // we have a converter to use to convert the strign 
+            // value of into something the set method expects.
+            final Converter converter = (Converter)converters.get(arg);
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException, 
+                               ClassIntrospectionException, ConversionException {
+                        m.invoke(parent, new Object[] {converter.convert(value, arg)});
+                    }
+                };
+        }
+        // simplest case - setAttribute expects String
+        else if (java.lang.String.class.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new String[] {value});
+                    }
+                };
+
+        // now for the primitive types, use their wrappers
+        } else if (java.lang.Character.class.equals(arg)
+                   || java.lang.Character.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Character[] {new Character(value.charAt(0))});
+                    }
+
+                };
+        } else if (java.lang.Byte.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Byte[] {new Byte(value)});
+                    }
+
+                };
+        } else if (java.lang.Short.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Short[] {new Short(value)});
+                    }
+
+                };
+        } else if (java.lang.Integer.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Integer[] {new Integer(value)});
+                    }
+
+                };
+        } else if (java.lang.Long.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Long[] {new Long(value)});
+                    }
+
+                };
+        } else if (java.lang.Float.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Float[] {new Float(value)});
+                    }
+
+                };
+        } else if (java.lang.Double.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, new Double[] {new Double(value)});
+                    }
+
+                };
+
+        } else if (java.lang.Boolean.class.equals(arg) 
+                   || java.lang.Boolean.TYPE.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException {
+                        m.invoke(parent, 
+                                 new Boolean[] {new Boolean(toBoolean(value))});
+                    }
+
+                };
+
+        // Class doesn't have a String constructor but a decent factory method
+        } else if (java.lang.Class.class.equals(arg)) {
+            return new AttributeSetter() {
+                    public void set(Object parent, String value) 
+                        throws InvocationTargetException, IllegalAccessException, ClassIntrospectionException {
+                        try {
+                            m.invoke(parent, new Class[] {Class.forName(value)});
+                        } catch (ClassNotFoundException ce) {
+                            throw new ClassIntrospectionException(ce);
+                        }
+                    }
+                };
+        // worst case. look for a public String constructor and use it
+        } else {
+
+            try {
+                final Constructor c = 
+                    arg.getConstructor(new Class[] {java.lang.String.class});
+
+                return new AttributeSetter() {
+                        public void set(Object parent, 
+                                        String value) 
+                            throws InvocationTargetException, IllegalAccessException, ClassIntrospectionException {
+                            try {
+                                m.invoke(parent, new Object[] {c.newInstance(new String[] {value})});
+                            } catch (InstantiationException ie) {
+                                throw new ClassIntrospectionException(ie);
+                            }
+                        }
+                    };
+                
+            } catch (NoSuchMethodException nme) {
+            }
+        }
+        
+        return null;
+    }
+
+    /**
+     * extract the name of a property from a method name - subtracting
+     * a given prefix.  
+     */
+    private String getPropertyName(String methodName, String prefix) {
+        int start = prefix.length();
+        return methodName.substring(start).toLowerCase();
+    }
+
+    private interface NestedCreator {
+        public Object create(Object parent) 
+            throws InvocationTargetException, IllegalAccessException, InstantiationException;
+    }
+    private interface AttributeSetter {
+        public void set(Object parent, String value)
+            throws InvocationTargetException, IllegalAccessException, 
+                   ClassIntrospectionException, ConversionException;
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ConversionException.java

@@ -0,0 +1,144 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+
+import java.io.*;
+
+/**
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ConversionException extends Exception {
+    /** 
+     * Exception that might have caused this one. 
+     */
+    private Throwable cause = null;
+
+    /**
+     * Constructs an exception with the given descriptive message.
+     * @param msg Description of or information about the exception.
+     */
+    public ConversionException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public ConversionException(String msg, Throwable cause) {
+        super(msg);
+        this.cause = cause;
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     * @param cause Exception that might have caused this one.
+     */
+    public ConversionException(Throwable cause) {
+        super(cause.toString());
+        this.cause = cause;
+    }
+
+    /**
+     * Returns the nested exception.
+     *
+     * @return the underlying exception
+     */
+    public Throwable getCause() {
+        return cause;
+    }
+
+    /**
+     * Print the stack trace to System.err
+     */
+    public void printStackTrace() {
+        printStackTrace(System.err);
+    }
+    
+    /**
+     * Print the stack trace to the given PrintStream
+     *
+     * @param ps the PrintStream onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintStream ps) {
+        synchronized (ps) {
+            ps.println(this);
+            if (cause != null) {
+                ps.println("--- Nested Exception ---");
+                cause.printStackTrace(ps);
+            }
+        }
+    }
+    
+    /**
+     * Print the stack trace to the given PrintWriter
+     *
+     * @param pw the PrintWriter onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintWriter pw) {
+        synchronized (pw) {
+            pw.println(this);
+            if (cause != null) {
+                pw.println("--- Nested Exception ---");
+                cause.printStackTrace(pw);
+            }
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/Converter.java

@@ -0,0 +1,67 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+/**
+ * Convert between a string and a data type
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public interface Converter {
+    /**
+     * Convert a string from the value given to an instance of the given type.
+     */
+    Object convert(String value, Class type) throws ConversionException;
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ConverterDefinition.java

@@ -0,0 +1,144 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A Converter definition defines a class which will convert
+ * a string into an instance of a particular type of class. Converters
+ * are typically only needed when some context information is 
+ * required to perform the conversion.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class ConverterDefinition {
+    /** The URL of the library which defines this converter */
+    private URL converterLibraryURL;
+     
+    /** The converter's class name */
+    private String converterClassName;
+    
+    /** The converted class returned by this converter */
+    private String targetClassName;
+    
+    /** The converter class loaded from the loader on demand.
+     */
+    private Class converterClass = null;
+    
+    /** The class to which this converter converts.
+     */
+    private Class targetClass = null;
+    
+    /** The converters's class loader. */
+    private ClassLoader converterClassLoader;
+    
+    public ConverterDefinition(URL converterLibraryURL, String converterClassName, 
+                               String targetClassName, ClassLoader converterClassLoader) {
+        this.converterLibraryURL = converterLibraryURL;
+        this.converterClassName = converterClassName;
+        this.targetClassName = targetClassName;
+        this.converterClassLoader = converterClassLoader;
+    }
+    
+    /**
+     * Get the name of the class that this converter will return.
+     */
+    public String getTargetClassName() {
+        return targetClassName;
+    }
+    
+    /**
+     * Get the classname of the converter that is being defined.
+     */
+    public String getConverterClassName() {
+        return converterClassName;
+    }
+    
+    /**
+     * Get the URL where this converter was defined.
+     *
+     * @returns a URL of the lib defintion file
+     */
+    public URL getLibraryURL() {
+        return converterLibraryURL;
+    }
+    
+    /**
+     * Get the converter class
+     *
+     * @return a class object for this converter
+     */
+    public synchronized Class getConverterClass() throws ClassNotFoundException {
+        if (converterClass == null) {
+            converterClass = converterClassLoader.loadClass(converterClassName);
+        }
+        return converterClass;
+    }
+    
+    /**
+     * Get the converter class
+     *
+     * @return a class object for this converter
+     */
+    public synchronized Class getTargetClass() throws ClassNotFoundException {
+        if (targetClass == null) {
+            targetClass = converterClassLoader.loadClass(targetClassName);
+        }
+        return targetClass;
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/execution/ExecutionException.java

@@ -0,0 +1,125 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+import org.apache.ant.core.support.*;
+import java.io.*;
+
+/**
+ * An ExecutiuonException indicates a problem during 
+ * the execution of the build files tasks
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ExecutionException extends AntException {
+    /**
+     * Constructs an exception with the given descriptive message.
+     *
+     * @param msg Description of or information about the exception.
+     */
+    public ExecutionException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given descriptive message and a location
+     * in a file.
+     * @param msg Description of or information about the exception.
+     * @param location Location in the project file where the error occured.
+     */
+    public ExecutionException(String msg, Location location) {
+        super(msg, location);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     *
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public ExecutionException(String msg, Throwable cause) {
+        super(msg, cause);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause and a location in a file.
+     * @param msg Description of or information about the exception.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ExecutionException(String msg, Throwable cause, Location location) {
+        super(msg, cause, location);
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     *
+     * @param cause Exception that might have caused this one.
+     */
+    public ExecutionException(Throwable cause) {
+        super(cause);
+    }
+
+    /**
+     * Constructs an exception with the given exception as
+     * a root cause and a location in a file.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ExecutionException(Throwable cause, Location location) {
+        super(cause, location);
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ExecutionFrame.java

@@ -0,0 +1,590 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+import org.apache.ant.core.model.*;
+import org.apache.ant.core.support.*;
+
+import java.util.*;
+import java.net.*;
+
+/**
+ * An ExecutionFrame is the state of a project during an execution. 
+ * The ExecutionFrame contains the data values set by Ant tasks as
+ * they are executed, including task definitions, property values, etc.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ExecutionFrame {
+    /** The Project that this execiton frame is processing */
+    private Project project = null;
+    
+    /** The base URL for this frame. This is derived from the 
+        Project's source URL and it's base attribute. */
+    private URL baseURL = null;
+    
+    /** The task defs that this frame will use to process tasks */
+    private Map taskDefs = new HashMap();
+    
+    /** The imported frames of this frame. For each project imported by this frame's
+        project, a corresponding ExecutionFrame is created. */
+    private Map importedFrames = new HashMap();
+    
+    /** BuildEvent support used to fire events and manage listeners */
+    private BuildEventSupport eventSupport = new BuildEventSupport();
+    
+    /** The context of this execution. This contains all data object's
+        created by tasks that have been executed */
+    private Map dataValues = new HashMap();
+    
+    /** Introspector objects used to configure ExecutionTasks from the Task models.*/
+    private Map introspectors = new HashMap();
+    
+    /** Type converters for this executionFrame. Converters are used when configuring
+        Tasks to handle special type conversions. */
+    private Map converters = new HashMap();
+    
+    /** The namespace under which this execution frame lives in the hierarchical
+        project namespace - null for the root namespace */
+    private String namespace;
+    
+    public ExecutionFrame(Project project, Map taskDefs, Map converterDefs,
+                          String namespace) throws ConfigException {
+        this.project = project;
+        this.taskDefs = taskDefs;
+        this.namespace = namespace;
+
+        try {        
+            String base = project.getBase();
+            if (base == null) {
+                baseURL = project.getSourceURL();
+            }
+            else {
+                base = base.trim();
+                if (!base.endsWith("/")) {
+                    base += "/";
+                }
+                baseURL = new URL(project.getSourceURL(), base);
+            }            
+        }
+        catch (MalformedURLException e) {
+            throw new ConfigException("Project's base value \"" + project.getBase() 
+                                      + "\" is not valid", e, project.getLocation());
+        }                                      
+        
+        // We create a set of converters from the converter definitions we
+        // have been given and initialise them. They should be AntConverters
+        setupConverters(converterDefs);
+        
+        for (Iterator i = project.getImportedProjectNames(); i.hasNext();) {
+            String importName = (String)i.next();
+            Project importedProject = project.getImportedProject(importName);
+            String importNamespace 
+                = namespace == null ? importName : namespace + ":" + importName;
+            ExecutionFrame importedFrame 
+                = new ExecutionFrame(importedProject, taskDefs, converterDefs, importNamespace);
+            importedFrames.put(importName, importedFrame);
+        }
+    }
+
+    public URL getBaseURL() {
+        return baseURL;
+    }
+
+    private void setupConverters(Map converterDefs) throws ConfigException {
+        converters = new HashMap();
+        for (Iterator i = converterDefs.values().iterator(); i.hasNext(); ) {
+            ConverterDefinition converterDef = (ConverterDefinition)i.next();
+            boolean targetLoaded = false;
+            try {
+                Class targetClass = converterDef.getTargetClass();
+                targetLoaded = false;
+                Class converterClass = converterDef.getConverterClass();
+                Converter converter = (AntConverter)converterClass.newInstance();
+                if (converter instanceof AntConverter) {
+                    ((AntConverter)converter).init(this);
+                }
+                converters.put(targetClass, converter);
+            }
+            catch (ClassNotFoundException e) {
+                if (targetLoaded) {
+                    throw new ConfigException("Unable to load converter class for " 
+                                              + converterDef.getConverterClassName()
+                                              + " in converter from " + converterDef.getLibraryURL()
+                                              , e);
+                }
+                else {
+                    throw new ConfigException("Unable to load target class " 
+                                              + converterDef.getTargetClassName()
+                                              + " in converter from " + converterDef.getLibraryURL()
+                                              , e);
+                }
+            }
+            catch (InstantiationException e) {
+                throw new ConfigException("Unable to instantiate converter class " 
+                                          + converterDef.getTargetClassName()
+                                          + " in converter from " + converterDef.getLibraryURL()
+                                          , e);
+            }
+            catch (IllegalAccessException e) {
+                throw new ConfigException("Unable to access converter class " 
+                                          + converterDef.getTargetClassName()
+                                          + " in converter from " + converterDef.getLibraryURL()
+                                          , e);
+            }
+        }
+    }
+    
+    public void addBuildListener(BuildListener listener) {
+        eventSupport.addBuildListener(listener);
+    }
+    
+    public void removeBuildListener(BuildListener listener) {
+        eventSupport.removeBuildListener(listener);
+    }
+
+    /**
+     * Get the project associated with this execution frame.
+     *
+     * @return the project associated iwth this execution frame.
+     */
+    public Project getProject() {
+        return project;
+    }
+    
+
+    /**
+     * Get the names of the frames representing imported projects.
+     *
+     * @return an iterator which returns the names of the imported frames.
+     */
+    public Iterator getImportedFrameNames() {
+        return importedFrames.keySet().iterator();
+    }
+    
+
+    /**
+     * Get the frames representing imported projects.
+     *
+     * @return an iterator which returns the imported ExeuctionFrames..
+     */
+    public Iterator getImportedFrames() {
+        return importedFrames.values().iterator();
+    }
+    
+    /**
+     * Get an imported frame by name
+     *
+     * @param importName the name under which the frame was imported.
+     *
+     * @return the ExecutionFrame asscociated with the given import name or null 
+     *         if there is no such project.
+     */
+    public ExecutionFrame getImportedFrame(String importName) {
+        return (ExecutionFrame)importedFrames.get(importName);
+    }
+    
+    /**
+     * Get the location of this frame in the namespace hierarchy
+     *
+     * @return the location of this frame within the project import
+     *         namespace hierarchy.
+     */
+    public String getNamespace() {
+        return namespace;
+    }
+    
+    /**
+     * Get the fully qualified name of something with respect to this 
+     * execution frame.
+     * 
+     * @param name the unqualified name.
+     * 
+     * @return the fully qualified version of the given name
+     */
+    public String getQualifiedName(String name) {
+        return namespace == null ? name : namespace + ":" + name;
+    }
+    
+    /**
+     * Get the relative name of something with respect to this 
+     * execution frame.
+     * 
+     * @param fullname the fully qualified name.
+     * 
+     * @return the relative version of the given name
+     */
+    public String getRelativeName(String fullname) {
+        if (namespace == null) {
+            return fullname;
+        }
+        int index = fullname.indexOf(namespace);
+        if (index != 0) {
+            return fullname;
+        }
+        
+        return fullname.substring(namespace.length() + 1);
+    }
+    
+    /**
+     * Execute the given target's tasks
+     *
+     * @param the name of the target within this frame that is to be executed.
+     */
+    public void executeTargetTasks(String targetName) throws ExecutionException, ConfigException {
+        Target target = project.getTarget(targetName);
+        try {
+            Iterator taskIterator = target.getTasks();
+            eventSupport.fireTargetStarted(this, target);
+            executeTasks(taskIterator);
+            eventSupport.fireTargetFinished(this, target, null);
+        }
+        catch (RuntimeException e) {
+            eventSupport.fireTargetFinished(this, target, e);
+            throw e;
+        }
+    }
+    
+    /**
+     * Initialise the frame by executing the project level tasks if any
+     */
+    public void initialise() throws ExecutionException, ConfigException {
+        Iterator taskIterator = project.getTasks();
+        executeTasks(taskIterator);
+    }
+
+
+    private ExecutionTask getConfiguredExecutionTask(TaskElement model) 
+        throws ConfigException, ExecutionException {
+
+        String taskType = model.getType();
+        TaskDefinition taskDefinition = (TaskDefinition)taskDefs.get(taskType);
+        if (taskDefinition == null) {
+            throw new ConfigException("There is no task defintion for tasks of type <" 
+                                      + taskType + ">", model.getLocation());
+        }
+        
+        try {
+            Class executionTaskClass = taskDefinition.getExecutionTaskClass();
+            ExecutionTask executionTask = (ExecutionTask)executionTaskClass.newInstance();
+            executionTask.setExecutionFrame(this);
+            executionTask.setBuildEventSupport(eventSupport);
+            executionTask.setBuildElement(model);
+            configureElement(executionTask, model);
+            return executionTask;
+        }
+        catch (ClassNotFoundException e) {
+            throw new ConfigException("Execution class " + taskDefinition.getTaskClassName()
+                                         + " was not found", e, model.getLocation());
+        }
+        catch (InstantiationException e) {
+            throw new ConfigException("Unable to instantiate execution class "
+                                          + taskDefinition.getTaskClassName(), 
+                                          e, model.getLocation());
+        }
+        catch (IllegalAccessException e) {
+            throw new ConfigException("Unable to access execution class "
+                                          + taskDefinition.getTaskClassName(), 
+                                          e, model.getLocation());
+        }
+    }        
+   
+    /**
+     * Run the tasks returned by the give iterator
+     *
+     * @param taskIterator the iterator giving the tasks to execute
+     */
+    public void executeTasks(Iterator taskIterator) throws ExecutionException, ConfigException {
+        Task task = null;
+        try {
+            while (taskIterator.hasNext()) {
+                task = (Task)taskIterator.next();
+                try {
+                    ExecutionTask executionTask = getConfiguredExecutionTask(task);
+                    eventSupport.fireTaskStarted(this, task);
+                    executionTask.execute();
+                }
+                catch (ExecutionException e) {
+                    if (e.getLocation() == null || e.getLocation() == Location.UNKNOWN_LOCATION) {
+                        e.setLocation(task.getLocation());
+                    }
+                    throw e;
+                }
+                catch (ConfigException e) {
+                    if (e.getLocation() == null || e.getLocation() == Location.UNKNOWN_LOCATION) {
+                        e.setLocation(task.getLocation());
+                    }
+                    throw e;
+                }
+                eventSupport.fireTaskFinished(this, task, null);
+            }
+        }
+        catch (RuntimeException e) {
+            eventSupport.fireTaskFinished(this, task, e);
+            throw e;
+        }
+    }        
+
+    private void configureElement(Object element, TaskElement model) 
+        throws ExecutionException, ConfigException {
+
+        try {
+            ClassIntrospector introspector = getIntrospector(element.getClass());
+                
+            // start by setting the attributes of this element
+            for (Iterator i = model.getAttributeNames(); i.hasNext();) {
+                String attributeName = (String)i.next();
+                String attributeValue = model.getAttributeValue(attributeName);
+                introspector.setAttribute(element, attributeName, 
+                                          replacePropertyRefs(attributeValue));
+            }
+            
+            String modelText = model.getText().trim();
+            if (modelText.length() != 0) {
+                introspector.addText(element, replacePropertyRefs(modelText));
+            }
+
+            // now do the nested elements
+            for (Iterator i = model.getNestedElements(); i.hasNext();) {
+                TaskElement nestedElementModel = (TaskElement)i.next();
+                if (element instanceof TaskContainer &&
+                    !introspector.supportsNestedElement(nestedElementModel.getType())) {
+                    
+                    ExecutionTask nestedExecutionTask 
+                        = getConfiguredExecutionTask(nestedElementModel);
+                        
+                    TaskContainer container = (TaskContainer)element;
+                    container.addExecutionTask(nestedExecutionTask);
+                }
+                else {                        
+                    Object nestedElement 
+                        = introspector.createElement(element, nestedElementModel.getType());
+                    configureElement(nestedElement, nestedElementModel);
+                }                    
+            }
+        }
+        catch (ClassIntrospectionException e) {
+            throw new ExecutionException(e, model.getLocation());
+        }
+        catch (ConversionException e) {
+            throw new ExecutionException(e, model.getLocation());
+        }
+    }
+
+    private ClassIntrospector getIntrospector(Class c) {
+        if (introspectors.containsKey(c)) {
+            return (ClassIntrospector)introspectors.get(c);
+        }
+        ClassIntrospector introspector = new ClassIntrospector(c, converters);
+        introspectors.put(c, introspector);
+        return introspector;
+    }
+                            
+    /**
+     * Replace ${} style constructions in the given value with the string value of
+     * the corresponding data types.
+     *
+     * @param value the string to be scanned for property references.
+     */
+    public String replacePropertyRefs(String value) throws ExecutionException {
+        if (value == null) {
+            return null;
+        }
+
+        List fragments = new ArrayList();
+        List propertyRefs = new ArrayList();
+        parsePropertyString(value, fragments, propertyRefs);
+
+        StringBuffer sb = new StringBuffer();
+        Iterator i = fragments.iterator();
+        Iterator j = propertyRefs.iterator();
+        while (i.hasNext()) {
+            String fragment = (String)i.next();
+            if (fragment == null) {
+                String propertyName = (String)j.next();
+                if (!isDataValueSet(propertyName)) {
+                    throw new ExecutionException("Property " + propertyName + " has not been set");
+                }
+                fragment = getDataValue(propertyName).toString();
+            }
+            sb.append(fragment);
+        }                        
+        
+        return sb.toString();
+    }
+    
+
+    /**
+     * This method will parse a string containing ${value} style 
+     * property values into two list. The first list is a collection
+     * of text fragments, while the other is a set of string property names
+     * null entries in the first list indicate a property reference from the
+     * second list.
+     */
+    static public void parsePropertyString(String value, List fragments, List propertyRefs) 
+        throws ExecutionException {
+        int prev = 0;
+        int pos;
+        while ((pos = value.indexOf("$", prev)) >= 0) {
+            if (pos > 0) {
+                fragments.add(value.substring(prev, pos));
+            }
+
+            if( pos == (value.length() - 1)) {
+                fragments.add("$");
+                prev = pos + 1;
+            }
+            else if (value.charAt(pos + 1) != '{' ) {
+                fragments.add(value.substring(pos + 1, pos + 2));
+                prev = pos + 2;
+            } else {
+                int endName = value.indexOf('}', pos);
+                if (endName < 0) {
+                    throw new ExecutionException("Syntax error in property: " 
+                                                 + value );
+                }
+                String propertyName = value.substring(pos + 2, endName);
+                fragments.add(null);
+                propertyRefs.add(propertyName);
+                prev = endName + 1;
+            }
+        }
+
+        if (prev < value.length()) {
+            fragments.add(value.substring(prev));
+        }
+    }
+
+    /**
+     * Given a name of an object, get the frame relative from this frame that
+     * contains that object.
+     */
+    private ExecutionFrame getRelativeFrame(String name) throws ExecutionException {
+        int index = name.lastIndexOf(":");
+        if (index == -1) {
+            return this;
+        }
+        
+        ExecutionFrame currentFrame = this;
+        String relativeFrameName = name.substring(0, index);
+        StringTokenizer tokenizer = new StringTokenizer(relativeFrameName, ":");
+        while (tokenizer.hasMoreTokens()) {
+            String frameName = tokenizer.nextToken();
+            currentFrame = currentFrame.getImportedFrame(frameName);
+            if (currentFrame == null) {
+                throw new ExecutionException("The project " + frameName + " in " 
+                                             + name + " was not found");
+            }
+        }
+        
+        return currentFrame;
+    }
+
+    /**
+     * Get the name of an object in its frame
+     */
+    private String getNameInFrame(String name) {
+        int index = name.lastIndexOf(":");
+        if (index == -1) {
+            return name;
+        }
+        return name.substring(index+1);
+    }
+
+    /**
+     * Set a value in this frame or any of its imported frames
+     */
+    public void setDataValue(String name, Object value) throws ExecutionException {
+        ExecutionFrame frame = getRelativeFrame(name);
+        frame.setDirectDataValue(getNameInFrame(name), value);
+    }
+    
+    /**
+     * Get a value from this frame or any imported frame
+     */
+    private Object getDataValue(String name) throws ExecutionException {
+        ExecutionFrame frame = getRelativeFrame(name);
+        return frame.getDirectDataValue(getNameInFrame(name));
+    }
+    
+    /**
+     * Set a value in this frame only
+     */
+    private void setDirectDataValue(String name, Object value) {
+        dataValues.put(name, value);
+    }
+    
+    /**
+     * Get a value from this frame
+     */
+    private Object getDirectDataValue(String name) {
+        return dataValues.get(name);
+    }
+
+    /**
+     * Indicate if a data value has been set
+     */
+    public boolean isDataValueSet(String name) throws ExecutionException {
+        ExecutionFrame frame = getRelativeFrame(name);
+        return frame.isDirectDataValueSet(getNameInFrame(name));
+    }
+        
+    /**
+     * Indicate if a data value has been set in this frame
+     */
+    private boolean isDirectDataValueSet(String name) {
+        return dataValues.containsKey(name);
+    }
+        
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ExecutionManager.java

@@ -0,0 +1,317 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+
+import org.apache.ant.core.model.*;
+import org.apache.ant.core.support.*;
+import java.util.*;
+
+/**
+ * The ExecutionManager manages the execution of Ant. It will create
+ * ExecutionFrames to handle the various imported projects, the 
+ * data values associated with those projects. Before the ExecutionManager
+ * can be used, it must be initialised with a set of Ant libraries. These 
+ * will contain task definitions, aspect definitions, etc.
+ * 
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ExecutionManager implements BuildListener {
+    private static final String VISITING = "VISITING";
+    private static final String VISITED = "VISITED";
+
+    private HashMap taskDefs = new HashMap();
+    private HashMap converterDefs = new HashMap();
+    private Project project;
+    private ExecutionFrame mainFrame;
+    private Map namespaceMap = null;
+    private List frameInitOrder = null;
+    
+    private BuildEventSupport eventSupport = new BuildEventSupport();
+    
+    public void addBuildListener(BuildListener listener) {
+        eventSupport.addBuildListener(listener);
+    }
+    
+    public void removeBuildListener(BuildListener listener) {
+        eventSupport.removeBuildListener(listener);
+    }
+
+    /** 
+     * Forward any events to our listeners.
+     */
+    public void processBuildEvent(BuildEvent event) {
+        eventSupport.forwardEvent(event);
+    }
+
+    public void addLibraries(AntLibrary[] libraries) throws ConfigException {
+        for (int i = 0; i < libraries.length; ++i) {
+            addLibrary(libraries[i]);
+        }
+    }
+    
+    public void addLibrary(AntLibrary library) throws ConfigException {
+        for (Iterator i = library.getTaskDefinitions(); i.hasNext(); ) {
+            TaskDefinition taskDefinition = (TaskDefinition)i.next();
+            addTaskDefinition(taskDefinition);
+        }
+        for (Iterator i = library.getConverterDefinitions(); i.hasNext(); ) {
+            ConverterDefinition converterDef = (ConverterDefinition)i.next();
+            addConverterDefinition(converterDef);
+        }
+    }
+
+    public void addTaskDefinition(TaskDefinition taskDefinition) throws ConfigException {
+        String taskName = taskDefinition.getName();
+        if (taskDefs.containsKey(taskName)) {
+            String message = "Task " + taskName + " is defined twice" +
+                             ", in " + ((TaskDefinition)taskDefs.get(taskName)).getLibraryURL() +
+                             " and " + taskDefinition.getLibraryURL();
+            throw new ConfigException(message, new Location(taskDefinition.getLibraryURL().toString()));
+        }
+        taskDefs.put(taskName, taskDefinition);
+    }
+    
+    public void addConverterDefinition(ConverterDefinition converterDef) throws ConfigException {
+        String targetClassname = converterDef.getTargetClassName();
+        if (converterDefs.containsKey(targetClassname)) {
+            String message = "Converter for " + targetClassname + " is defined twice" +
+                             ", in " + ((ConverterDefinition)converterDefs.get(targetClassname)).getLibraryURL() +
+                             " and " + converterDef.getLibraryURL();
+            throw new ConfigException(message, new Location(converterDef.getLibraryURL().toString()));
+        }
+        converterDefs.put(targetClassname, converterDef);
+    }
+    
+    public void setProject(Project project) throws ConfigException {
+        this.project = project;
+        mainFrame = new ExecutionFrame(project, (Map)taskDefs.clone(), 
+                                       (Map)converterDefs.clone(), null);
+        namespaceMap = new HashMap();
+        frameInitOrder = new ArrayList();
+        setupFrame(mainFrame);
+        
+        // We iterate through all nodes of all projects and make sure every node is OK
+        Map state = new HashMap();
+        Stack visiting = new Stack();
+        List dependencyOrder = new ArrayList();
+
+        checkFrameTargets(mainFrame, dependencyOrder, state, visiting);
+    }
+
+    /**
+     * Check whether the targets in the given execution frame and its subframes are OK
+     */
+    private void checkFrameTargets(ExecutionFrame frame, List dependencyOrder, 
+                                   Map state, Stack visiting) 
+            throws ConfigException {
+        // get the targets and just iterate through them.
+        for (Iterator i = frame.getProject().getTargets(); i.hasNext();) {
+            Target target = (Target)i.next();
+            fillinDependencyOrder(frame, target.getName(),
+                                  dependencyOrder, state, visiting);
+        }
+        
+        // Now do the subframes.
+        for (Iterator i = frame.getImportedFrames(); i.hasNext();) {
+            ExecutionFrame importedFrame = (ExecutionFrame)i.next();
+            checkFrameTargets(importedFrame, dependencyOrder, state, visiting);
+        }
+    }
+    
+    private void setupFrame(ExecutionFrame frame) {
+        frame.addBuildListener(this);
+        
+        String namespace = frame.getNamespace();
+        if (namespace != null) {
+            namespaceMap.put(namespace, frame);
+        }
+        for (Iterator i = frame.getImportedFrameNames(); i.hasNext();) {
+            String importName = (String)i.next();
+            setupFrame(frame.getImportedFrame(importName));
+        }
+        frameInitOrder.add(frame);
+    }
+    
+    public void runBuild(List targetNames) throws AntException {
+        Throwable buildFailureCause = null;
+        try {
+            eventSupport.fireBuildStarted(this, project);
+            // we initialise each execution frame
+            for (Iterator i = frameInitOrder.iterator(); i.hasNext();) {
+                ExecutionFrame frame = (ExecutionFrame)i.next();
+                frame.initialise();
+            }
+            if (targetNames.isEmpty()) {
+                // we just execute the default target if any
+                String defaultTarget = project.getDefaultTarget();
+                if (defaultTarget != null) {
+                    executeTarget(defaultTarget);
+                }
+            }
+            else {
+                for (Iterator i = targetNames.iterator(); i.hasNext();) {
+                    executeTarget((String)i.next());
+                }
+            }
+            eventSupport.fireBuildFinished(this, project, null);
+        }
+        catch (RuntimeException e) {
+            buildFailureCause = e;
+            throw e;
+        }
+        catch (AntException e) {
+            buildFailureCause = e;
+            throw e;
+        }
+        finally {
+            eventSupport.fireBuildFinished(this, project, buildFailureCause);
+        }
+    }
+
+    private ExecutionFrame getFrame(String name) {
+        int namespaceIndex = name.lastIndexOf(":");
+        if (namespaceIndex == -1) {
+            return mainFrame;
+        }
+        return (ExecutionFrame)namespaceMap.get(name.substring(0, namespaceIndex));
+    }
+    
+    public void executeTarget(String targetName) throws ExecutionException, ConfigException {
+        // to execute a target we must determine its dependencies and 
+        // execute them in order.
+        Map state = new HashMap();
+        Stack visiting = new Stack();
+        List dependencyOrder = new ArrayList();
+        ExecutionFrame startingFrame = getFrame(targetName);
+        fillinDependencyOrder(startingFrame, startingFrame.getRelativeName(targetName),
+                              dependencyOrder, state, visiting);
+
+        // Now tell each frame to execute the target
+        for (Iterator i = dependencyOrder.iterator(); i.hasNext();) {
+            String fullTargetName = (String)i.next();
+            ExecutionFrame frame = getFrame(fullTargetName);
+            frame.executeTargetTasks(frame.getRelativeName(fullTargetName));
+        }
+    }
+    
+    private void fillinDependencyOrder(ExecutionFrame frame, String targetName, 
+                                       List dependencyOrder, Map state,
+                                       Stack visiting) throws ConfigException {
+        String fullTargetName = frame.getQualifiedName(targetName); 
+        if (state.get(fullTargetName) == VISITED) {
+            return;
+        }
+        Target target = frame.getProject().getTarget(targetName);                                       
+        if (target == null) {
+            StringBuffer sb = new StringBuffer("Target `");
+            sb.append(targetName);
+            sb.append("' does not exist in this project. ");
+            if (!visiting.empty()) {
+                String parent = (String)visiting.peek();
+                sb.append("It is used from target `");
+                sb.append(parent);
+                sb.append("'.");
+            }
+
+            throw new ConfigException(new String(sb), frame.getProject().getLocation());
+        }
+        
+        state.put(fullTargetName, VISITING);
+        visiting.push(fullTargetName);
+        for (Iterator i = target.getDependencies(); i.hasNext(); ) {
+            String dependency = (String)i.next();
+            String fullyQualifiedName = frame.getQualifiedName(dependency);
+            ExecutionFrame dependencyFrame = getFrame(fullyQualifiedName);
+            if (dependencyFrame == null) {
+                StringBuffer sb = new StringBuffer("Target `");
+                sb.append(dependency);
+                sb.append("' does not exist in this project. ");
+                throw new ConfigException(new String(sb), target.getLocation());
+            }
+            
+            String dependencyState = (String)state.get(fullyQualifiedName);
+            if (dependencyState == null) {
+                fillinDependencyOrder(dependencyFrame, dependencyFrame.getRelativeName(fullyQualifiedName),
+                                      dependencyOrder, state, visiting);
+            }
+            else if (dependencyState == VISITING) {
+                String circleDescription
+                    = getCircularDesc(dependency, visiting);
+                throw new ConfigException(circleDescription, target.getLocation());
+            }
+        }
+        
+        state.put(fullTargetName, VISITED);
+        String poppedNode = (String)visiting.pop();
+        if (poppedNode != fullTargetName) {
+            throw new ConfigException("Problem determining dependencies " + 
+                                        " - expecting '" + fullTargetName + 
+                                        "' but got '" + poppedNode + "'");
+        }
+        dependencyOrder.add(fullTargetName);                                        
+    }
+                                
+    private String getCircularDesc(String end, Stack visitingNodes) {
+        StringBuffer sb = new StringBuffer("Circular dependency: ");
+        sb.append(end);
+        String c;
+        do {
+            c = (String)visitingNodes.pop();
+            sb.append(" <- ");
+            sb.append(c);
+        } while(!c.equals(end));
+        return new String(sb);
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/execution/ExecutionTask.java

@@ -0,0 +1,150 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import org.apache.ant.core.model.*;
+import org.apache.ant.core.support.*;
+import java.util.*;
+import java.net.URL;
+
+/**
+ * An ExecutionTask is the execution time equivalent of the Task
+ * object in the Ant project model. Subclasses of ExecutionTask are
+ * created by Task writers to implement particular, desired 
+ * functionality
+ *
+ * An ExecutionTask subclass is created for a particular task type. 
+ * The data from the task model is introspected into the ExecutionTask
+ * which is then executed.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public abstract class ExecutionTask {
+    private ExecutionFrame frame = null;
+    private Location location = Location.UNKNOWN_LOCATION;
+    private BuildEventSupport eventSupport;
+    private BuildElement buildElement;
+
+    void setExecutionFrame(ExecutionFrame frame) {
+        this.frame = frame;
+    }
+
+    /**
+     * Get the ExecutionFrame in which this ExecutionTask is being executed.
+     * to which this task belongs
+     *
+     * @return the execution task's ExecutionFrame.
+     */
+    public ExecutionFrame getExecutionFrame() {
+        return frame;
+    }
+
+    /**
+     * Configure the event support to be used to fire events
+     */
+    void setBuildEventSupport(BuildEventSupport eventSupport) {
+        this.eventSupport = eventSupport;
+    }
+    
+    /**
+     * Associate this ExecutionTask with a buildElement in the
+     * project model
+     */
+    void setBuildElement(BuildElement buildElement) {
+        this.buildElement = buildElement;
+    }
+    
+    /**
+     * Log a message with the default (INFO) priority.
+     *
+     * @param msg the message to be logged.
+     */
+    public void log(String msg) {
+        log(msg, BuildEvent.MSG_INFO);
+    }
+
+    /**
+     * Log a mesage with the give priority.
+     *
+     * @param the message to be logged.
+     * @param msgLevel the message priority at which this message is to be logged.
+     */
+    public void log(String msg, int msgLevel) {
+        eventSupport.fireMessageLogged(this, buildElement, msg, msgLevel);
+    }
+
+    /**
+     * Called by the project to let the task initialize properly. 
+     *
+     * @throws ExecutionException if someting goes wrong with the build
+     */
+    public void init() throws ExecutionException {}
+
+    /**
+     * Called by the frame to let the task do it's work. 
+     *
+     * @throws ExecutionException if someting goes wrong with the build
+     */
+    abstract public void execute() throws ExecutionException;
+
+    /**
+     * Returns the file location where this task was defined.
+     */
+    public Location getLocation() {
+        return buildElement.getLocation();
+    }
+    
+}
+

proposal/mutant/src/main/org/apache/ant/core/execution/InputProvider.java

@@ -0,0 +1,77 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.execution;
+
+/*
+ * An input provider is an object which is provided to Ant's core
+ * execution system to provide input from the user. Typically command
+ * line based clients will request input from the console whilst 
+ * GUI clients may pop up an input dialog. Unattended operation may
+ * be able to source input from some form of script.
+ */
+public interface InputProvider {
+    /** 
+     * Request input from the user
+     *
+     * @param prompt a string which is used to prompt the user for input.
+     * @param defaultInput the default value initially supplied to the user
+     * @param timeout a timeout in milliseconds which some clients may use
+     *        to either accept the default or to fail.
+     *
+     * @return a string of the user's input if the user provided any.
+     *
+     * @throws ExecutionException if the no input could be obtained from the user
+     */
+    String userInput(String prompt, String defaultInput) throws ExecutionException;
+}

proposal/mutant/src/main/org/apache/ant/core/execution/TaskContainer.java

@@ -0,0 +1,72 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A TaskContainer is an object which can contain and manage 
+ * ExecutionTasks.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public interface TaskContainer {
+    /**
+     * Add a task to the container.
+     */
+    void addExecutionTask(ExecutionTask executionTask) throws ExecutionException;
+}
+

proposal/mutant/src/main/org/apache/ant/core/execution/TaskDefinition.java

@@ -0,0 +1,125 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.execution;
+
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A Task definition provides the information necessary to execute
+ * a task implementation.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class TaskDefinition {
+    /** The URL of the library which defines this task */
+    private URL taskLibraryURL;
+     
+    /** The task's name */
+    private String taskName;
+    
+    /** The task's class */
+    private String taskClassName;
+    
+    /** The task's class loaded from the loader on demand. */
+    private Class taskClass = null;
+    
+    /** The task's class loader. */
+    private ClassLoader taskClassLoader;
+    
+    public TaskDefinition(URL taskLibraryURL, String taskName, String taskClassName, 
+                          ClassLoader taskClassLoader) {
+        this.taskLibraryURL = taskLibraryURL;
+        this.taskName = taskName;
+        this.taskClassName = taskClassName;
+        this.taskClassLoader = taskClassLoader;
+    }
+    
+    /**
+     * Get the name of the task that is being defined.
+     */
+    public String getName() {
+        return taskName;
+    }
+    
+    /**
+     * Get the classname of the task that is being defined.
+     */
+    public String getTaskClassName() {
+        return taskClassName;
+    }
+    
+    /**
+     * Get the URL where this task was defined.
+     *
+     * @returns a URL of the lib defintion file
+     */
+    public URL getLibraryURL() {
+        return taskLibraryURL;
+    }
+    
+    /**
+     * Get the task class for this task
+     *
+     * @return a class object for this task
+     */
+    public synchronized Class getExecutionTaskClass() throws ClassNotFoundException {
+        if (taskClass == null) {
+            taskClass = taskClassLoader.loadClass(taskClassName);
+        }
+        return taskClass;
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/model/BuildElement.java

@@ -0,0 +1,127 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.model;
+
+import java.util.*;
+import org.apache.ant.core.support.*;
+
+/**
+ * A BuildElement is an element of a build file and has a location
+ * within that file.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class BuildElement {
+    /**
+     * The aspects defined for this element.
+     */
+    private Map aspects;
+
+    /**
+     * The location of this element
+     */
+    private Location location;
+    
+    /**
+     * A comment associated with this element, if any
+     *
+     */
+    private String comment;
+    
+    /**
+     * Create a build element giving its location.
+     *
+     * @param location identifies where this element is defined
+     */
+    public BuildElement(Location location) {
+        this.location = location;
+    }
+    
+    /**
+     * Get the location of the source where this element is defined
+     *
+     * @return the element's location
+     */
+    public Location getLocation() {
+        return location;
+    }
+    
+    /**
+     * Set a comment associated with this element
+     *
+     * @param comment the comment to be associated with this element.
+     */
+    public void setComment(String comment) {
+        this.comment = comment;
+    }
+    
+    /**
+     * Get the comment associated with this element.
+     *
+     * @return the element's comment which may be null.
+     */
+    public String getComment() {
+        return comment;
+    }
+    
+    /**
+     * Set the aspects of this element
+     *
+     * @param aspects a Map of apects that relate to this build element.
+     */
+    public void setAspects(Map aspects) {
+        this.aspects = aspects;
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/model/Project.java

@@ -0,0 +1,267 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.model;
+
+import org.apache.ant.core.support.*;
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A project is a collection of targets and global tasks. A project
+ * may reference objects in other projects using named references of 
+ * the form project:object
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Project extends BuildElement {
+    /** The default target in this project. */
+    private String defaultTarget = null;
+
+    /** The base URL of this project. Relative locations are relative to this base.*/
+    private String base;
+    
+    /**
+     * The name of this project when referenced by a script within this project. 
+     */
+    private String name;
+    
+    /**
+     * These are the targets which belong to the project. They
+     * will have interdependencies which are used to determine
+     * which targets need to be executed before a given target.
+     */
+    private Map targets = new HashMap();
+    
+    /**
+     * The global tasks for this project. These are the tasks that will get executed
+     * whenever an execution context is associated with this project.
+     */
+    private List tasks = new ArrayList();
+    
+    /**
+     * The projects imported into this project. Each imported project is
+     * given a name which is used to identify access to that project's
+     * elements.
+     */
+    private Map importedProjects = new HashMap(); 
+
+    /**
+     * The URL where the project is defined.
+     * 
+     */
+    private URL sourceURL;
+
+    /**
+     * Create a Project
+     *
+     * @param sourceURL the URL where the project is defined.
+     * @param location the location of this element within the source.
+     */
+    public Project(URL sourceURL, Location location) {
+        super(location);
+        this.sourceURL = sourceURL;
+    }
+
+    /**
+     * Get the URL where this project is defined
+     *
+     * @return the project source URL
+     */
+    public URL getSourceURL() {
+        return sourceURL;
+    }
+        
+    /**
+     * Add a target to the project.
+     *
+     * @param target the Target to be added
+     * 
+     * @throws ProjectModelException if a target with the same name already exists.
+     */
+    public void addTarget(Target target) throws ProjectModelException {
+        if (targets.containsKey(target.getName())) {
+            throw new ProjectModelException("A target with name '" + target.getName() +
+                                            "' has already been defined in this project", 
+                                            target.getLocation());
+        }                                            
+        targets.put(target.getName(), target);
+    }
+    
+    /**
+     * Set the defautl target of this project.
+     *
+     * @param defaultTarget the name of the defaultTarget of this project.
+     */
+    public void setDefaultTarget(String defaultTarget) {
+        this.defaultTarget = defaultTarget;
+    }
+    
+    /**
+     * Get the Project's default Target, if any
+     *
+     * @return the project's defautl target or null if there is no default.
+     */
+    public String getDefaultTarget() {
+        return defaultTarget;
+    }
+
+    /**
+     * Set the base URL for this project.
+     *
+     * @param base the baseURL for this project.
+     */
+    public void setBase(String base) {
+        this.base = base;
+    }
+        
+    /**
+     * Get the base URL for this project.
+     *
+     * @return the baseURL for this project as a string.
+     */
+    public String getBase() {
+        return base;
+    }
+        
+    /**
+     * Set the name of this project.
+     *
+     * @param name the name for this project.
+     */
+    public void setName(String name) {
+        this.name = name;
+    }
+        
+
+    /**
+     * Add a task to the list of global tasks for this project.
+     *
+     * @param task a task to be executed when an execution context
+     * is associated with the Project (a non-target task)
+     */
+    public void addTask(Task task) {
+        tasks.add(task);
+    }
+    
+    /**
+     * Import a project to be referenced using the given name.
+     *
+     * @param importName the name under which the project will be referenced.
+     * @param project the imported project.
+     *
+     * @throws ProjectModelException if an existing project has already 
+     *                               been imported with that name.
+     */
+    public void importProject(String importName, Project project) 
+            throws ProjectModelException {
+        if (importedProjects.containsKey(importName)) {
+            throw new ProjectModelException("A project has already been imported with name '" + 
+                                            importName + "'");
+        }
+        importedProjects.put(importName, project);
+    }
+    
+    /**
+     * Get the targets in this project.
+     *
+     * @return an iterator returning Target objects.
+     */
+    public Iterator getTargets() {
+        return targets.values().iterator();
+    }
+    
+    /**
+     * Get the target with the given name
+     *
+     * @param targetName the name of the desired target.
+     *
+     * @return the target with the given name or null if there is no
+     *         such target.
+     */
+    public Target getTarget(String targetName) {
+        return (Target)targets.get(targetName);
+    }
+    
+    /**
+     * Get the name sof the imported projects.
+     *
+     * @return an iterator which returns the name sof the imported projects.
+     */
+    public Iterator getImportedProjectNames() {
+        return importedProjects.keySet().iterator();
+    }
+    
+    /**
+     * Get an imported project by name
+     *
+     * @param importName the name under which the project was imported.
+     *
+     * @return the project asscociated with the given import name or null 
+     *         if there is no such project.
+     */
+    public Project getImportedProject(String importName) {
+        return (Project)importedProjects.get(importName);
+    }
+    
+    /**
+     * Get the initialisation tasks for this project
+     *
+     * @return an iterator over the set of tasks for this project.
+     */
+    public Iterator getTasks() {
+        return tasks.iterator();
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/model/ProjectModelException.java

@@ -0,0 +1,129 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.model;
+
+import org.apache.ant.core.support.*;
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A project model exception is thrown when an operation is attempted
+ * which would violate the integrity of the Project/Target/Task object
+ * model
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class ProjectModelException extends AntException {
+    /**
+     * Constructs an exception with the given descriptive message.
+     *
+     * @param msg Description of or information about the exception.
+     */
+    public ProjectModelException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given descriptive message and a location
+     * in a file.
+     * @param msg Description of or information about the exception.
+     * @param location Location in the project file where the error occured.
+     */
+    public ProjectModelException(String msg, Location location) {
+        super(msg, location);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     *
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public ProjectModelException(String msg, Throwable cause) {
+        super(msg, cause);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause and a location in a file.
+     * @param msg Description of or information about the exception.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ProjectModelException(String msg, Throwable cause, Location location) {
+        super(msg, cause, location);
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     *
+     * @param cause Exception that might have caused this one.
+     */
+    public ProjectModelException(Throwable cause) {
+        super(cause);
+    }
+
+    /**
+     * Constructs an exception with the given exception as
+     * a root cause and a location in a file.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ProjectModelException(Throwable cause, Location location) {
+        super(cause, location);
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/model/Target.java

@@ -0,0 +1,136 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.model;
+
+import java.util.*;
+import org.apache.ant.core.support.*;
+
+/**
+ * A Target is a collection of tasks. It may have
+ * dependencies on other targets
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Target extends BuildElement {
+    private List dependencies = new ArrayList();
+    
+    /**
+     * This target's list of tasks
+     */
+    private List tasks = new ArrayList();
+    
+    /**
+     * The target's name.
+     */
+    private String name;
+    
+    /**
+     * Construct the target, given its name
+     *
+     * @param location the location of the element
+     * @param name the target's name.
+     */
+    public Target(Location location, String name) {
+        super(location);
+        this.name = name;
+    }
+    
+    /**
+     * Get this target's name.
+     *
+     * @return the target's name.
+     */
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Add a task to this target
+     *
+     * @param task the task to be added to the target.
+     */
+    public void addTask(Task task) {
+        tasks.add(task);
+    }
+    
+    /**
+     * Add a dependency to this target
+     *
+     * @param dependency the name of a target upon which this target 
+     *                   depends
+     */
+    public void addDependency(String dependency) {
+        dependencies.add(dependency);
+    }
+
+    /**
+     * Get this target's dependencies.
+     *   
+     * @return an iterator over the target's dependencies.
+     */
+    public Iterator getDependencies() {
+        return dependencies.iterator();
+    }
+    
+    /**
+     * Get the tasks for this target
+     *
+     * @return an iterator over the set of tasks for this target.
+     */
+    public Iterator getTasks() {
+        return tasks.iterator();
+    }
+    
+}
+

proposal/mutant/src/main/org/apache/ant/core/model/Task.java

@@ -0,0 +1,75 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.model;
+
+import org.apache.ant.core.support.*;
+import java.util.*;
+
+/**
+ * A Task is a holder for Task information (attributes and elements)
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Task extends TaskElement {
+    /**
+     * Create a Task of the given type
+     *
+     * @param location the location of the element
+     * @param type the task's type
+     */
+    public Task(Location location, String type) {
+        super(location, type);
+    }
+    
+}

proposal/mutant/src/main/org/apache/ant/core/model/TaskElement.java

@@ -0,0 +1,169 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.model;
+
+import java.util.*;
+import org.apache.ant.core.support.*;
+
+/**
+ * A TaskElement is a holder for Task configuration information.
+ * TaskElements may be grouped into a hierarchy to capture
+ * any level of Task element nesting.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class TaskElement extends BuildElement {
+    /** The attributes of this task element */
+    private Map attributes = new HashMap();
+
+    /**
+     * The task's name or type
+     */
+    private String type;
+    
+    /**
+     * The task elements that make up this task.
+     */
+    private List taskElements = new ArrayList();
+    
+    /** The content (text) of this task */
+    private String text = "";
+    
+    /**
+     * Create a Task of the given type
+     *
+     * @param location the location of the element
+     * @param type the task element's type
+     */
+    public TaskElement(Location location, String type) {
+        super(location);
+        this.type = type;
+    }
+    
+    /**
+     * Add text to this task.
+     *
+     * @param text the element text to add.
+     */
+    public void addText(String text) {
+        this.text += text;
+    }
+
+    /**
+     * Get the text of this task
+     *
+     * @return the task's text.
+     */
+     public String getText() {
+        return text;
+    }
+     
+    /**
+     * Add a task element to this task
+     * 
+     * @param taskElement the task element to be added.
+     */
+    public void addTaskElement(TaskElement taskElement) {
+        taskElements.add(taskElement);
+    }
+
+    /**
+     * Get an iterator over this element's nexted elements
+     *
+     * @return an iterator which provides TaskElement instances
+     */
+    public Iterator getNestedElements() {
+        return taskElements.iterator();
+    }
+    
+    /**
+     * Get the type of this task element
+     *
+     * @return the element's type
+     */
+    public String getType() {
+        return type;
+    }
+
+    /**
+     * Add an attribute to this task element
+     *
+     * @param attributeName the name of the attribute
+     * @param attributeValue the attribute's value.
+     */
+    public void addAttribute(String attributeName, String attributeValue) {
+        attributes.put(attributeName, attributeValue);
+    }
+    
+    /**
+     * Get an iterator over the task's attributes
+     *
+     * @return an iterator which provide's attribute names
+     */
+    public Iterator getAttributeNames() {
+        return attributes.keySet().iterator();
+    }
+    
+    /**
+     * Get the value of an attribute.
+     *
+     * @param attributeName the name of the attribute
+     *
+     * @return the value of the attribute or null if there is no such attribute.
+     */
+    public String getAttributeValue(String attributeName) {
+        return (String)attributes.get(attributeName);
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/support/AntClassLoader.java

@@ -0,0 +1,147 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.support;
+
+import java.util.*;
+import java.net.*;
+import java.io.*;
+
+/**
+ * A ReverseURLclassLoader is a type of URL classloader which reverse the standard
+ * lookup order to load things from the URLs first and then to use the parent class
+ * loader only if the class does not exist in the URLs.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class AntClassLoader extends URLClassLoader {
+    private String debugLabel = null;
+    private boolean debug = false;
+
+    private void dumpURLs() {
+        if (debug && debugLabel != null) {
+            System.out.println(debugLabel + ": loader URLs");
+            URL[] urls = getURLs();
+            for (int i = 0; i < urls.length; ++i) {
+                System.out.println(debugLabel + ": URL: " + urls[i]);
+            }
+        }
+    }        
+    
+    public AntClassLoader(URL[] urls) {
+        super(urls);
+    }
+
+    public AntClassLoader(URL[] urls, String debugLabel) {
+        super(urls);
+        this.debugLabel = debugLabel;
+    }
+
+    public AntClassLoader(URL[] urls,
+                          ClassLoader parent) {
+        super(urls, parent);
+    }
+    
+    public AntClassLoader(URL[] urls,
+                          ClassLoader parent, String debugLabel) {
+        super(urls, parent);
+        this.debugLabel = debugLabel;
+    }
+    
+    public void setDebug(boolean debug) {
+        this.debug = debug;
+        dumpURLs();    
+    }
+
+    protected Class loadClass(String name, boolean resolve) 
+            throws ClassNotFoundException {
+        if (debug && debugLabel != null) {                
+            System.out.println(debugLabel + ": Trying to load class " + name);
+        }
+
+        Class c = findLoadedClass(name);
+        if (c == null) {
+            try {
+                c = findClass(name);
+                if (debug && debugLabel != null) {
+                    System.out.println(debugLabel + ": Found class " + name + " in this loader");
+                }
+            } catch (ClassNotFoundException e) {
+                c = super.loadClass(name, resolve);
+                if (debug && debugLabel != null) {
+                    System.out.println(debugLabel + ": Found class " + name + " in parent loader");
+                }
+                return c;
+            }
+        }
+        if (resolve) {
+            resolveClass(c);
+        }
+        return c;
+    }
+        
+    public void addURL(URL url) {
+        super.addURL(url);
+    }
+
+    public URL getResource(String name) {
+        URL url = findResource(name);
+        if (url == null) {
+            url = super.getResource(name);
+        }
+        
+        return url;
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/support/AntException.java

@@ -0,0 +1,205 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.support;
+
+
+import java.io.*;
+
+/**
+ * An AntException indicates some exceptional case has been encountered in
+ * the processing of Ant. AntExceptions may accept a Throwable as a
+ * cause allowing exceptions to be nested
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public abstract class AntException extends Exception {
+    /** 
+     * Exception that might have caused this one. 
+     */
+    private Throwable cause = null;
+
+    /**
+     * The location of the element which is associated with this exception if known.
+     */
+    private Location location = Location.UNKNOWN_LOCATION;
+    
+    /**
+     * Constructs an exception with the given descriptive message.
+     * @param msg Description of or information about the exception.
+     */
+    public AntException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public AntException(String msg, Throwable cause) {
+        super(msg);
+        this.cause = cause;
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause and a location in a file.
+     * @param msg Description of or information about the exception.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public AntException(String msg, Throwable cause, Location location) {
+        this(msg, cause);
+        setLocation(location);
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     * @param cause Exception that might have caused this one.
+     */
+    public AntException(Throwable cause) {
+        super(cause.toString());
+        this.cause = cause;
+    }
+
+    /**
+     * Constructs an exception with the given descriptive message and a location
+     * in a file.
+     * @param msg Description of or information about the exception.
+     * @param location Location in the project file where the error occured.
+     */
+    public AntException(String msg, Location location) {
+        super(msg);
+        setLocation(location);
+    }
+
+    /**
+     * Constructs an exception with the given exception as
+     * a root cause and a location in a file.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public AntException(Throwable cause, Location location) {
+        this(cause);
+        setLocation(location);
+    }
+
+    /**
+     * Returns the nested exception.
+     *
+     * @return the underlying exception
+     */
+    public Throwable getCause() {
+        return cause;
+    }
+
+    /**
+     * Sets the file location where the error occured.
+     */
+    public void setLocation(Location location) {
+        if (location == null) {
+            this.location = Location.UNKNOWN_LOCATION;
+        }
+        else {
+            this.location = location;
+        }
+    }
+
+    /**
+     * Returns the file location where the error occured.
+     */
+    public Location getLocation() {
+        return location;
+    }
+
+    /**
+     * Print the stack trace to System.err
+     */
+    public void printStackTrace() {
+        printStackTrace(System.err);
+    }
+    
+    /**
+     * Print the stack trace to the given PrintStream
+     *
+     * @param ps the PrintStream onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintStream ps) {
+        synchronized (ps) {
+            ps.println(this);
+            if (cause != null) {
+                ps.println("--- Nested Exception ---");
+                cause.printStackTrace(ps);
+            }
+        }
+    }
+    
+    /**
+     * Print the stack trace to the given PrintWriter
+     *
+     * @param pw the PrintWriter onto which the stack trace 
+     *           of this exception is to be printed
+     */
+    public void printStackTrace(PrintWriter pw) {
+        synchronized (pw) {
+            pw.println(this);
+            if (cause != null) {
+                pw.println("--- Nested Exception ---");
+                cause.printStackTrace(pw);
+            }
+        }
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/support/AntLocator.java

@@ -0,0 +1,331 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.support;
+
+import java.util.*;
+import java.net.*;
+import java.io.*;
+
+/**
+ * The Ant Locator is used to find various Ant components without
+ * requiring the user to maintain environment properties. 
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class AntLocator {
+    private AntLocator() {}
+    
+    /**
+     * Get the URL for the given class's load location.
+     *
+     * @param theClass the class whose loadURL is desired.
+     * @return a URL which identifies the component from which this class was loaded.
+     *
+     * @throws LocationException if the class' URL cannot be constructed.
+     */
+    static public URL getClassLocationURL(Class theClass) 
+            throws LocationException {
+        String className = theClass.getName().replace('.', '/') + ".class";
+        URL classRawURL = theClass.getClassLoader().getResource(className);
+        
+        try {
+            String fileComponent = classRawURL.getFile();
+            if (classRawURL.getProtocol().equals("file")) {
+                // Class comes from a directory of class files rather than
+                // from a jar. 
+                int classFileIndex = fileComponent.lastIndexOf(className);
+                if (classFileIndex != -1) {
+                    fileComponent = fileComponent.substring(0, classFileIndex);
+                }
+                
+                return new URL("file:" + fileComponent);
+            }
+            else if (classRawURL.getProtocol().equals("jar")) {
+                // Class is coming from a jar. The file component of the URL
+                // is actually the URL of the jar file
+                int classSeparatorIndex = fileComponent.lastIndexOf("!");
+                if (classSeparatorIndex != -1) {
+                    fileComponent = fileComponent.substring(0, classSeparatorIndex);
+                }
+                
+                return new URL(fileComponent);
+            }
+            else {
+                // its running out of something besides a jar. We just return the Raw
+                // URL as a best guess
+                return classRawURL;
+            }
+        }
+        catch (MalformedURLException e) {
+            throw new LocationException(e);
+        }
+    }
+
+
+    /**
+     * Get the location of AntHome
+     *
+     * @return the URL containing AntHome.
+     *
+     * @throws LocationException if Ant's home cannot be determined.
+     */
+    static public URL getAntHome() throws LocationException {
+        try {
+            URL libraryURL = getLibraryURL();
+            if (libraryURL != null) {
+                return new URL(libraryURL, "..");
+            }
+            else {
+                return null;
+            }
+        }
+        catch (MalformedURLException e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    /**
+     * Get a URL to the Ant core jar. Other jars can be located 
+     * from this as relative URLs
+     *
+     * @return a URL containing the Ant core or null if the core cannot be determined.
+     *
+     * @throws LocationException if the URL of the core.jar cannot be determined.
+     */
+    static public URL getCoreURL() throws LocationException {
+        return getClassLocationURL(AntLocator.class);
+    }
+    
+    /**
+     * Get a URL to the Ant Library directory.
+     *
+     * @throws LocationException if the location of the Ant library directory cannot 
+     *         be determined
+     */
+    static public URL getLibraryURL() throws LocationException {
+        URL coreURL = getCoreURL();
+        
+        try {
+            if (coreURL.getProtocol().equals("file") &&
+                coreURL.getFile().endsWith("/")) {
+                // we are running from a set of classes. This should only happen
+                // in an Ant build situation. We use some embedded knowledge to
+                // locate the lib directory
+                File coreClassDirectory = new File(coreURL.getFile());
+                File libDirectory = coreClassDirectory.getParentFile().getParentFile();
+                if (!libDirectory.exists()) {
+                    throw new LocationException("Ant library directory " + libDirectory + 
+                                                   " does not exist");
+                }
+                return (new File(libDirectory, "lib")).toURL();
+            }
+            else {
+                String coreURLString = coreURL.toString();
+                int index = coreURLString.lastIndexOf("/");
+                if (index != -1) {
+                    coreURLString = coreURLString.substring(0, index+1);
+                }
+                return new URL(coreURLString);
+            }
+        }
+        catch (MalformedURLException e) {
+            throw new LocationException(e);
+        }
+    }
+    
+    /**
+     * Get a classloader with which to load the SAX parser
+     *
+     * @return the classloader to use to load Ant's XML parser
+     *
+     * @throws LocationException if the location of the parser jars 
+     *                              could not be determined.
+     */
+    static public ClassLoader getParserClassLoader(Properties properties) 
+            throws LocationException {
+        // we look for the parser directory based on a system property first
+        String parserURLString = properties.getProperty(Constants.PropertyNames.PARSER_URL);
+        URL parserURL = null;
+        if (parserURLString != null) {
+            try {
+                parserURL = new URL(parserURLString);
+            }
+            catch (MalformedURLException e) {
+                throw new LocationException("XML Parser URL " + parserURLString + 
+                                               " is malformed.", e);
+            }
+        }
+        else {
+            try {
+                parserURL = new URL(getLibraryURL(), "parser/");
+            }
+            catch (Exception e) {
+                // ignore - we will just use the default class loader.
+            }
+        }
+
+        if (parserURL != null) {
+            try {
+                URL[] parserURLs = null;
+                if (parserURL.getProtocol().equals("file")) {
+                    // build up the URLs for each jar file in the 
+                    // parser directory
+                    parserURLs = getDirectoryJarURLs(new File(parserURL.getFile()));
+                }
+                else {
+                    // we can't search the URL so we look for a known parser relative to
+                    // that URL
+                    String defaultParser = properties.getProperty(Constants.PropertyNames.DEFAULT_PARSER);
+                    if (defaultParser == null) {
+                        defaultParser = Constants.Defaults.DEFAULT_PARSER;
+                    }
+                    
+                    parserURLs = new URL[1];
+                    parserURLs[0] = new URL(parserURL, defaultParser);
+                    
+                }
+                
+                return new AntClassLoader(parserURLs, "parser");
+            }
+            catch (MalformedURLException e) {
+                throw new LocationException(e);
+            }
+        }
+        
+        return AntLocator.class.getClassLoader();
+    }
+
+    /**
+     * Get an array of URLs for each file matching the given set of extensions
+     *
+     * @param directory the local directory
+     * @param extensions the set of extensions to be returned
+     *
+     * @return an array of URLs for the file found in the directory.
+     */
+    static public URL[] getDirectoryURLs(File directory, final Set extensions) {
+        URL[] urls = new URL[0];
+        
+        if (!directory.exists()) {
+            return urls;
+        }
+        
+        File[] jars = directory.listFiles(new FilenameFilter() {
+                                                public boolean accept(File dir, String name) {
+                                                    int extensionIndex = name.lastIndexOf(".");
+                                                    if (extensionIndex == -1) {
+                                                        return false;
+                                                    }
+                                                    String extension = name.substring(extensionIndex);
+                                                    return extensions.contains(extension);
+                                                }
+                                            });
+        urls = new URL[jars.length];
+        for (int i = 0; i < jars.length; ++i) {
+            try {
+                urls[i] = jars[i].toURL();
+            }
+            catch (MalformedURLException e) {
+                // just ignore
+            }
+        }
+        return urls;
+    }
+    
+
+
+    
+    /**
+     * Get an array of URLs for each jar file in a local directory.
+     *
+     * @param directory the local directory
+     *
+     * @return an array of URLs for the jars found in the directory.
+     */
+    static private URL[] getDirectoryJarURLs(File directory) {
+        HashSet extensions = new HashSet();
+        extensions.add(".jar");
+        return getDirectoryURLs(directory, extensions);        
+    }
+    
+    /**
+     * Get the Core Class Loader. The core requires a SAX parser which must come from the
+     * given classloader
+     *
+     * @throws LocationException if the location of the core ant classes could 
+     *                              not be determined
+     */
+    static public AntClassLoader getCoreClassLoader(Properties properties) 
+            throws LocationException {
+        URL[] coreURL = new URL[1];
+        coreURL[0] = getCoreURL();
+        AntClassLoader coreLoader 
+            = new AntClassLoader(coreURL, getParserClassLoader(properties), "core");
+        URL libraryURL = getLibraryURL();
+        if (libraryURL != null && libraryURL.getProtocol().equals("file")) {
+            // we can search this
+
+            URL[] optionalURLs = getDirectoryJarURLs(new File(libraryURL.getFile(), "optional"));
+            for (int i = 0; i < optionalURLs.length; ++i) {
+                coreLoader.addURL(optionalURLs[i]);
+            }
+            
+        }
+        
+        return coreLoader;          
+    }        
+}
+

proposal/mutant/src/main/org/apache/ant/core/support/ConfigException.java

@@ -0,0 +1,125 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+package org.apache.ant.core.support;
+
+import java.io.*;
+
+/**
+ * A ConfigException indicates a problem with 
+ * Ant's configuration.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public class ConfigException extends AntException {
+    /**
+     * Constructs an exception with the given descriptive message.
+     *
+     * @param msg Description of or information about the exception.
+     */
+    public ConfigException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given descriptive message and a location
+     * in a file.
+     * @param msg Description of or information about the exception.
+     * @param location Location in the project file where the error occured.
+     */
+    public ConfigException(String msg, Location location) {
+        super(msg, location);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     *
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public ConfigException(String msg, Throwable cause) {
+        super(msg, cause);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause and a location in a file.
+     * @param msg Description of or information about the exception.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ConfigException(String msg, Throwable cause, Location location) {
+        super(msg, cause, location);
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     *
+     * @param cause Exception that might have caused this one.
+     */
+    public ConfigException(Throwable cause) {
+        super(cause);
+    }
+
+    /**
+     * Constructs an exception with the given exception as
+     * a root cause and a location in a file.
+     * @param cause Exception that might have cause this one.
+     * @param location Location in the project file where the error occured.
+     */
+    public ConfigException(Throwable cause, Location location) {
+        super(cause, location);
+    }
+
+}

proposal/mutant/src/main/org/apache/ant/core/support/Constants.java

@@ -0,0 +1,76 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.support;
+
+import java.util.*;
+import java.net.*;
+import java.io.*;
+
+/**
+ * Constants used by the Ant core
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Constants {
+    static public class PropertyNames {
+        static public final String PARSER_URL = "ant.parser.url";
+        static public final String DEFAULT_PARSER = "ant.parser.default";
+    }
+    
+    static public class Defaults {
+        static public final String DEFAULT_PARSER = "crimson.jar";
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/support/Location.java

@@ -0,0 +1,166 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.support;
+
+/**
+ * Stores the file name and line number in a file.
+ */
+public class Location {
+    /**
+     * The source URL to which this location relates.
+     */
+    private String source;
+    
+    /**
+     * The line number of this location within the source
+     */
+    private int lineNumber;
+    
+    /**
+     * The column number of this locatin within the source
+     */
+    private int columnNumber;
+
+    /**
+     * Standard unknown location constant;
+     */
+    public static final Location UNKNOWN_LOCATION = new Location();
+
+    /**
+     * Creates an "unknown" location.
+     */
+    private Location() {
+        this(null, 0, 0);
+    }
+
+    /**
+     * Creates a location consisting of a source location but no line number.
+     *
+     * @param source the source (URL) to which this location is associated.
+     */
+    public Location(String source) {
+        this(source, 1, 1);
+    }
+
+    /**
+     * Creates a location consisting of a source location and co-ordinates within that
+     * source
+     *
+     * @param source the source (URL) to which this location is associated.
+     * @param lineNumber the line number of this location
+     * @param columnNumber the column number of this location
+     */
+    public Location(String source, int lineNumber, int columnNumber) {
+        this.source = source;
+        this.lineNumber = lineNumber;
+        this.columnNumber = columnNumber;
+    }
+
+    /**
+     * Returns the source name, line number and a trailing space. An error
+     * message can be appended easily. For unknown locations, returns
+     * an empty string.
+     *
+     * @return a suitable string representation of the location
+     */
+    public String toString() {
+        StringBuffer buf = new StringBuffer();
+
+        if (source != null) {
+            if (source.startsWith("file:")) {
+                buf.append(source.substring(5));
+            }
+            else {
+                buf.append(source);
+            }
+
+            if (lineNumber != 0) {
+                buf.append(":");
+                buf.append(lineNumber);
+            }
+
+            buf.append(": ");
+        }
+
+        return buf.toString();
+    }
+    
+    /**
+     * Get the source URL for this location
+     *
+     * @return a URL string 
+     */
+    public String getSourceURL() {
+        return source;
+    }
+    
+    /**
+     * Get the line number of this location
+     *
+     * @return an integer line number
+     */
+    public int getLineNumber() {
+        return lineNumber;
+    }
+
+    /**
+     * Get the column number of this location
+     *
+     * @return an integer column number
+     */
+    public int getColumnNumber() {
+        return columnNumber;
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/support/LocationException.java

@@ -0,0 +1,97 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.support;
+
+import java.util.*;
+import java.net.URL;
+
+/**
+ * A LocationException is thrown when there is a problem determining
+ * the location of an Ant component.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class LocationException extends AntException {
+    /**
+     * Constructs an exception with the given descriptive message.
+     *
+     * @param msg Description of or information about the exception.
+     */
+    public LocationException(String msg) {
+        super(msg);
+    }
+
+    /**
+     * Constructs an exception with the given message and exception as
+     * a root cause.
+     *
+     * @param msg Description of or information about the exception.
+     * @param cause Throwable that might have cause this one.
+     */
+    public LocationException(String msg, Throwable cause) {
+        super(msg, cause);
+    }
+
+    /**
+     * Constructs an exception with the given exception as a root cause.
+     *
+     * @param cause Exception that might have caused this one.
+     */
+    public LocationException(Throwable cause) {
+        super(cause);
+    }
+
+}
+

proposal/mutant/src/main/org/apache/ant/core/types/EnumeratedAttribute.java

@@ -0,0 +1,116 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.types;
+
+import org.apache.ant.core.execution.*;
+
+/**
+ * Helper class for attributes that can only take one of a fixed list
+ * of values.
+ *
+ * @author <a href="mailto:stefan.bodewig@epost.de">Stefan Bodewig</a> 
+ */
+public abstract class EnumeratedAttribute {
+
+    /** The value of this attribute. */
+    private String value;
+
+    /**
+     * This is the only method a subclass needs to implement.
+     *
+     * @return an array holding all possible values of the enumeration.
+     */
+    public abstract String[] getValues();
+
+    /**
+     * Set the value of the enumeration.
+     *
+     * Invoked by {@link org.apache.ant.core.execution.IntrospectionHelper IntrospectionHelper}.
+     *
+     * @param value the value of the enumeration
+     *
+     * @throws ExecutionException if the value is not value
+     */
+    public final void setValue(String value) throws ExecutionException {
+        if (!containsValue(value)) {
+            throw new ExecutionException(value + " is not a legal value for this attribute");
+        }
+        this.value = value;
+    }
+
+    /**
+     * Is this value included in the enumeration?
+     */
+    public final boolean containsValue(String value) {
+        String[] values = getValues();
+        if (values == null || value == null) {
+            return false;
+        }
+        
+        for (int i = 0; i < values.length; i++) {
+            if (value.equals(values[i])) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Retrieves the value.
+     */
+    public final String getValue() {
+        return value;
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/xml/AntLibParser.java

@@ -0,0 +1,258 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.xml;
+
+import java.io.*;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.*;
+import javax.xml.parsers.*;
+import org.apache.ant.core.support.*;
+import org.apache.ant.core.execution.*;
+import org.xml.sax.*;
+import org.xml.sax.helpers.DefaultHandler;
+
+/**
+ * Parses the TASK-INF/antlib.xml file of an ant library
+ * component. An Ant library may contains tasks, apsects and
+ * other ant plug in components
+ */ 
+public class AntLibParser {
+    public static final String TASK_ELEMENT = "taskdef";
+    public static final String CONVERTER_ELEMENT = "converter";
+    
+    /**
+     * The factory used to create SAX parsers.
+     */
+    private SAXParserFactory parserFactory;
+
+    /**
+     * Parse the library definition
+     *
+     * @param libSource the URL from where the library XML is read.
+     *
+     * @throws SAXParseException if there is a problem parsing the task definitions
+     */
+    public AntLibrary parseAntLibrary(URL libSource, ClassLoader componentLoader) 
+            throws ConfigException {
+        try {
+            parserFactory = SAXParserFactory.newInstance();
+            SAXParser saxParser = parserFactory.newSAXParser();
+            XMLReader xmlReader = saxParser.getXMLReader();
+
+            AntLibRootHandler rootHandler = new AntLibRootHandler(libSource, xmlReader, componentLoader);
+            saxParser.parse(libSource.toString(), rootHandler);
+            return rootHandler.getAntLibrary();
+        }
+        catch (SAXParseException e) {
+            throw new ConfigException(e.getMessage(), e, 
+                                      new Location(libSource.toString(), 
+                                                   e.getLineNumber(), e.getColumnNumber()));
+        }
+        catch (ParserConfigurationException e) {
+            throw new ConfigException("Unable to parse Ant library component", e, 
+                                      new Location(libSource.toString()));
+        }
+        catch (SAXException e) {
+            throw new ConfigException("Unable to parse Ant library component", e, 
+                                      new Location(libSource.toString()));
+        }
+        catch (IOException e) {
+            throw new ConfigException("Unable to parse Ant library component", e, 
+                                      new Location(libSource.toString()));
+        }
+    }
+    
+    /**
+     * The root handler handles the antlib element. An ant lib may
+     * contain a number of different types of elements
+     * <ul>
+     *    <li>taskdef</li>
+     *    <li>aspect</li>
+     *    <li>converter</li>
+     * </ul>
+     */
+    private class AntLibRootHandler extends RootHandler {
+        static private final int STATE_LOOKING_FOR_ROOT = 1;
+        static private final int STATE_ROOT_SEEN = 2;
+        static private final int STATE_FINISHED = 3;
+        
+        private int state = STATE_LOOKING_FOR_ROOT;
+        
+        /**
+         * The AntLibrary that will be defined by parsing the library's definition
+         * file.
+         */
+        private AntLibrary library = null;
+
+        private ClassLoader componentLoader = null;
+
+        /**
+         * Create an Ant Library Root Handler.
+         *
+         * @param taskdefSource the URL from where the task definitions exist
+         * @param reader the XML parser.
+         */
+        public AntLibRootHandler(URL taskdefSource, XMLReader reader, ClassLoader componentLoader) {
+            super(taskdefSource, reader);
+            this.componentLoader = componentLoader;
+        }
+    
+        /**
+         * Get the library which has been parsed.
+         *
+         * @return an AntLibary with the library definitions
+         */
+        public AntLibrary getAntLibrary() {
+            return library;
+        }
+
+        /**
+         * Start a new element in the root. This must be a taskdefs element
+         * All other elements are invalid.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            switch (state) {
+                case STATE_LOOKING_FOR_ROOT:
+                    if (qualifiedName.equals("antlib")) {
+                        state = STATE_ROOT_SEEN;
+                        library = new AntLibrary();
+                    }
+                    else {
+                        throw new SAXParseException("An Ant library component must start with an " +
+                                                    "<antlib> element and not with <" + 
+                                                     qualifiedName + ">", getLocator());
+                    }
+                    break;
+                case STATE_ROOT_SEEN:                                                     
+                    if (qualifiedName.equals(TASK_ELEMENT)) {
+                        createTaskDef(attributes);
+                    }
+                    else if (qualifiedName.equals(CONVERTER_ELEMENT)) {
+                        createConverterDef(attributes);
+                    } 
+                    else {
+                        throw new SAXParseException("Unrecognized element <" + 
+                                                     qualifiedName + "> in Ant library definition", getLocator());
+                    }
+                    break;
+            }
+        }
+        
+
+        public void createTaskDef(Attributes attributes) throws SAXParseException {
+            Set validAttributes = new HashSet();
+            validAttributes.add("name");
+            validAttributes.add("classname");
+            Map attributeValues 
+                = AttributeValidator.validateAttributes(TASK_ELEMENT, attributes, 
+                                                        validAttributes, getLocator());
+            String taskName = (String)attributeValues.get("name");
+            String className = (String)attributeValues.get("classname");
+            if (taskName == null) {
+                throw new SAXParseException("'name' attribute is required in a <" 
+                                            + TASK_ELEMENT + "> element",
+                                            getLocator());
+            }
+            if (className == null) {
+                throw new SAXParseException("'classname' attribute is required in a " + 
+                                            "<" + TASK_ELEMENT + "> element", getLocator());
+            }
+            
+            System.out.println("Adding taskdef for " + taskName);
+            TaskDefinition taskdef = new TaskDefinition(getSourceURL(), taskName, className, componentLoader);
+            library.addTaskDefinition(taskdef);
+        }                        
+            
+        public void createConverterDef(Attributes attributes) throws SAXParseException {
+            Set validAttributes = new HashSet();
+            validAttributes.add("target");
+            validAttributes.add("classname");
+            Map attributeValues 
+                = AttributeValidator.validateAttributes("convert", attributes, 
+                                                        validAttributes, getLocator());
+            String targetClassName = (String)attributeValues.get("target");
+            String className = (String)attributeValues.get("classname");
+            if (targetClassName == null) {
+                throw new SAXParseException("'target' attribute is required in a <" 
+                                            + CONVERTER_ELEMENT + "> element",
+                                            getLocator());
+            }
+            if (className == null) {
+                throw new SAXParseException("'classname' attribute is required in a " + 
+                                            "<" + CONVERTER_ELEMENT + "> element", getLocator());
+            }
+            
+            ConverterDefinition converterDef 
+                = new ConverterDefinition(getSourceURL(), className, targetClassName, componentLoader);
+            library.addConverterDefinition(converterDef);
+        }                        
+
+        public void endElement(String namespaceURI, String localName, String qName) {
+            if (state == STATE_ROOT_SEEN && qName.equals("antlib")) {
+                state = STATE_FINISHED;
+            }
+        }
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/core/xml/AttributeValidator.java

@@ -0,0 +1,112 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.xml;
+
+import org.xml.sax.helpers.DefaultHandler;
+import org.xml.sax.*;
+import java.util.*;
+
+
+/**
+ * Validates and extracts attribute values from a set of element attributes.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public abstract class AttributeValidator {
+    static public Map validateAttributes(String elementName, Attributes attributes, 
+                                          Set validAttributes, Locator locator) 
+        throws SAXParseException {
+            
+        return validateAttributes(elementName, attributes, null, validAttributes, locator);
+    }
+
+    static public Map validateAttributes(String elementName, Attributes attributes, Map aspects,
+                                          Set validAttributes, Locator locator) 
+        throws SAXParseException {
+            
+        Map attributeValues = new HashMap();    
+        Set invalidAttributes = new HashSet();
+        for (int i = 0; i < attributes.getLength(); ++i) {
+            String attributeName = attributes.getQName(i);
+            String attributeValue = attributes.getValue(i);
+            if (validAttributes.contains(attributeName)) {
+                attributeValues.put(attributeName, attributeValue);
+            }
+            else if (aspects != null && attributeName.indexOf(":") != -1) {
+                aspects.put(attributeName, attributeValue);
+            }
+            else {
+                invalidAttributes.add(attributeName);
+            }
+        }
+        
+        if (invalidAttributes.size() != 0) {
+            StringBuffer message = new StringBuffer();
+            boolean justOne = invalidAttributes.size() == 1;
+            message.append(justOne ? "The attribute " : "The attributes ");
+            for (Iterator i = invalidAttributes.iterator(); i.hasNext();) {
+                String attributeName = (String)i.next();
+                message.append(attributeName + " ");
+            }
+            message.append(justOne ? "is " : "are ");
+            message.append("not valid for the <" + elementName + "> element.");
+            
+            throw new SAXParseException(message.toString(), locator);
+        }
+        
+        return attributeValues;
+    }
+
+}

proposal/mutant/src/main/org/apache/ant/core/xml/ElementHandler.java

@@ -0,0 +1,109 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.xml;
+
+import org.xml.sax.helpers.DefaultHandler;
+import org.xml.sax.*;
+
+/**
+ * An Element Handler is a handler which handles a single element by becoming
+ * the handler for the parser while processing the element. Any sub elements 
+ * must be delegated to separate handlers. When this element is finished, 
+ * control returns to the parent handler.
+ */ 
+public abstract class ElementHandler extends DefaultHandler {
+    private XMLReader reader;
+    private ContentHandler parent;
+    private Locator locator;
+
+    public ElementHandler(XMLReader reader, ContentHandler parent,
+                          Locator locator) {
+        this.reader = reader;
+        this.parent = parent;
+        this.locator = locator;
+        reader.setContentHandler(this);
+    }
+
+    /**
+     * This element is finished - complete any necessary processing.
+     */
+    protected void finish() {
+    }
+
+    /**
+     * Get the XML Reader being used to parse the XML.
+     *
+     * @return the XML Reader.
+     */
+    protected XMLReader getXMLReader() {
+        return reader;
+    }
+    
+    /**
+     * Get the locator used to locate elements in the XML source as
+     * they are parsed.
+     *
+     * @return the locator object which can be used to determine an elements location
+     *         within the XML source
+     */
+    protected Locator getLocator() {
+        return locator;
+    }
+
+    public void endElement(String namespaceURI, String localName, String qName) {
+        finish();
+        reader.setContentHandler(parent);
+    }
+}

proposal/mutant/src/main/org/apache/ant/core/xml/RootHandler.java

@@ -0,0 +1,131 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.xml;
+
+import org.xml.sax.helpers.DefaultHandler;
+import org.xml.sax.*;
+import java.net.URL;
+
+/**
+ * Handle the root of a XML parse
+ */
+public abstract class RootHandler extends DefaultHandler {
+    /**
+     * Locator used to identify where in the build source particular elements
+     * occur.
+     */
+    private Locator locator;
+    
+    /**
+     * The actual XML parser used to parse the build source
+     */
+    private XMLReader reader;
+    
+    /**
+     * The URL from which the XML source is being read.
+     */
+    private URL sourceURL;
+
+    /**
+     * Create a Root Handler.
+     *
+     * @param sourceURL the URL containing the XML source
+     * @param reader the XML parser.
+     */
+    public RootHandler(URL sourceURL, XMLReader reader) {
+        this.sourceURL = sourceURL;
+        this.reader = reader;
+    }
+    
+    /**
+     * Set the locator to use when parsing elements. This is passed onto
+     * child elements.
+     *
+     * @param locator the locator for locating elements in the build source.
+     */
+    public void setDocumentLocator(Locator locator) {
+        this.locator = locator;
+    }
+
+    /**
+     * Get the XML Reader being used to parse the XML.
+     *
+     * @return the XML Reader.
+     */
+    protected XMLReader getXMLReader() {
+        return reader;
+    }
+    
+    /**
+     * Get the locator used to locate elements in the XML source as
+     * they are parsed.
+     *
+     * @return the locator object which can be used to determine an elements location
+     *         within the XML source
+     */
+    protected Locator getLocator() {
+        return locator;
+    }
+
+    /**
+     * Get the source URL
+     *
+     * @return a URL identifiying from where the XML is being read.
+     */
+    public URL getSourceURL() {
+        return sourceURL;
+    }
+}
+    

proposal/mutant/src/main/org/apache/ant/core/xml/XMLProjectParser.java

@@ -0,0 +1,904 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.core.xml;
+
+import java.io.*;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.*;
+import javax.xml.parsers.*;
+import org.apache.ant.core.model.*;
+import org.apache.ant.core.support.*;
+import org.xml.sax.*;
+import org.xml.sax.helpers.DefaultHandler;
+
+/**
+ * Parses a project from an XML source using a SAX Parser.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class XMLProjectParser {
+    private Stack recursionCheck = new Stack();
+    
+    /**
+     * The factory used to create SAX parsers.
+     */
+    private SAXParserFactory parserFactory;
+
+    static private Location getLocation(Locator locator) {
+        return new Location(locator.getSystemId(), locator.getLineNumber(),
+                            locator.getColumnNumber());
+    }                            
+
+    /**
+     * Parse a build file form the given URL.
+     *
+     * @param buildSource the URL from where the build source may be read.
+     *
+     * @throws SAXParseException if there is a problem parsing the build file.
+     */
+    public Project parseBuildFile(URL buildSource) 
+            throws ConfigException {
+        try {
+            parserFactory = SAXParserFactory.newInstance();
+            SAXParser saxParser = parserFactory.newSAXParser();
+            XMLReader xmlReader = saxParser.getXMLReader();
+
+            recursionCheck.push(buildSource);
+            ProjectRootHandler projectRootHandler 
+                = new ProjectRootHandler(buildSource, xmlReader);
+            saxParser.parse(buildSource.toString(), projectRootHandler);
+            return projectRootHandler.getProject();
+        }
+        catch (SAXParseException e) {
+            throw new ConfigException(e.getMessage(), e, 
+                                      new Location(buildSource.toString(), 
+                                                   e.getLineNumber(), e.getColumnNumber()));
+        }
+        catch (NoProjectReadException e) {
+            throw new ConfigException("No project defined in build source", e, 
+                                      new Location(buildSource.toString()));
+       }
+        catch (ParserConfigurationException e) {
+            throw new ConfigException("Unable to parse project: " + e.getMessage(), e, 
+                                      new Location(buildSource.toString()));
+        }
+        catch (SAXException e) {
+            throw new ConfigException("Unable to parse project: " + e.getMessage(), e, 
+                                      new Location(buildSource.toString()));
+        }
+        catch (IOException e) {
+            throw new ConfigException("Unable to parse project: " + e.getMessage(), e, 
+                                      new Location(buildSource.toString()));
+        }
+    }
+    
+    /**
+     * The root handler handles the start of parsing. This element looks for the 
+     * root element which must be a project element. It then delegates handling of the
+     * project element to a project handler from which it extracts the parsed project.
+     */
+    private class ProjectRootHandler extends RootHandler {
+        /**
+         * The project handler created to parse the project element.
+         */
+        ProjectHandler projectHandler;
+        
+        /**
+         * Create a Root Handler.
+         *
+         * @param buildSource the URL containing the build definition
+         * @param reader the XML parser.
+         */
+        public ProjectRootHandler(URL buildSource, XMLReader reader) {
+            super(buildSource, reader);
+        }
+
+        /**
+         * Start a new element in the root. This must be a project element
+         * All other elements are invalid.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                  Attributes attributes) throws SAXParseException {
+            if (qualifiedName.equals("project")) {
+                projectHandler = new ProjectHandler(getXMLReader(), this, 
+                                                    getLocator(), attributes, getSourceURL());
+            } else {
+                throw new SAXParseException("Build file should start with a <project> element not <" + 
+                                             qualifiedName + ">", getLocator());
+            }
+        }
+        
+        /**
+         * Get the project that has been parsed from the element
+         *
+         * @return the project that has been parsed from the build osurce
+         * 
+         * @throws NoProjectReadException thrown if no project was read in.
+         */
+        public Project getProject() throws NoProjectReadException {
+            if (projectHandler == null) {
+                throw new NoProjectReadException();
+            }
+            return projectHandler.getProject();
+        }
+    }
+    
+    /**
+     * Root Handler for include elements.
+     * 
+     * Includes must contain either a project (which is being extended) or 
+     * a fragment element which contains the fragment to be included.
+     */
+    private class IncludeRootHandler extends RootHandler {
+        /**
+         * The project into which the fragment is to be included.
+         */
+        private Project project;
+        
+        /**
+         * Create an Include Root Handler.
+         *
+         * @param buildSource the URL containing the fragment definition
+         * @param reader the XML parser.
+         * @param project the project into which the fragment's elements will be included.
+         */
+        public IncludeRootHandler(URL buildSource, XMLReader reader, Project project) {
+            super(buildSource, reader);
+            this.project = project;
+        }
+
+        /**
+         * Start a new element in the include root. This must be a project element
+         * or a fragment element. All other elements are invalid.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                  Attributes attributes) throws SAXParseException {
+            if (qualifiedName.equals("project") ||
+                qualifiedName.equals("fragment")) {
+                // if it is a fragment, it must have no attributes
+                // any project attributes are ignored
+                if (qualifiedName.equals("fragment") && attributes.getLength() != 0) {
+                    throw new SAXParseException("<fragment> element may not have any attributes", 
+                                                getLocator());
+                }                                                
+                new ProjectHandler(getXMLReader(), this, getLocator(), 
+                                   getSourceURL(), project);
+            } else {
+                throw new SAXParseException("An included file should contain either a " +
+                                            "<project> or <fragment> element and not a <" + 
+                                            qualifiedName + "> element", getLocator());
+            }
+        }
+    }
+    
+    /**
+     * Element to parse the project element.
+     *
+     * The project handler creates a number of different handlers to which it
+     * delegates processing of child elements.
+     */
+    private class ProjectHandler extends ElementHandler {
+        /**
+         * The project being parsed.
+         */
+        private Project project;
+        
+        /**
+         * The sourceURL for the current content being added to the project.
+         */
+        private URL sourceURL;
+
+        /**
+         * Create a ProjectHandler to read in a complete project.
+         * 
+         * @param xmlReader the XML parser being used to parse the project element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes the project element's attributes.
+         * @param projectSource the URL from which the XML source is being parsed.
+         */
+        public ProjectHandler(XMLReader xmlReader, ContentHandler parent,
+                              Locator locator, Attributes attributes, URL projectSource) 
+            throws SAXParseException {
+                
+            super(xmlReader, parent, locator);
+            this.sourceURL = projectSource;                            
+            project = new Project(projectSource, getLocation(locator));
+
+            String base = null;
+            String defaultTarget = null;
+            String projectName = null;
+            
+            Map aspects = new HashMap();
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.equals("base")) {
+                    base = attributeValue;
+                }
+                else if (attributeName.equals("default")) {
+                    defaultTarget = attributeValue;
+                }
+                else if (attributeName.equals("name")) {
+                    projectName = attributeValue;
+                }
+                else if (attributeName.indexOf(":") != -1) {
+                    // potential aspect attribute
+                    aspects.put(attributeName, attributeValue);
+                }
+                else {
+                    throw new SAXParseException("The attribute '" + attributeName + "' is not " + 
+                                                "supported by the <project> element", getLocator());
+                }
+            }
+            
+            project.setDefaultTarget(defaultTarget);
+            project.setBase(base);
+            project.setName(projectName);
+            project.setAspects(aspects);
+        }
+        
+        /**
+         * Create a Project handler for an included fragment. The elements
+         * from the fragment are added to the given project.
+         *
+         * @param xmlReader the XML parser being used to parse the project element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param includeSource the URL from which the XML source is being included.
+         * @param project the project to which the included fragments elements are added.
+         */
+        public ProjectHandler(XMLReader xmlReader, ContentHandler parent,
+                              Locator locator, URL includeSource, Project project) {
+            super(xmlReader, parent, locator);
+            this.sourceURL = includeSource;                            
+            this.project = project;
+        }
+        
+        /**
+         * Start a new element in the project. Project currently handle the 
+         * following elements
+         * <ul>
+         *   <li>import</li>
+         *   <li>include</li>
+         *   <li>target</li>
+         * </ul>
+         *
+         * Everything else is treated as a task.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            if (qualifiedName.equals("import")) {
+                ImportHandler importHandler 
+                    = new ImportHandler(getXMLReader(), this, getLocator(), 
+                                        attributes, sourceURL);
+                try {                                        
+                    project.importProject(importHandler.getImportName(), 
+                                      importHandler.getImportedProject());
+                }
+                catch (ProjectModelException e) {
+                    throw new SAXParseException(e.getMessage(), getLocator(), e);
+                }
+            }
+            else if (qualifiedName.equals("include")) {
+                IncludeHandler includeHandler 
+                    = new IncludeHandler(getXMLReader(), this, getLocator(), 
+                                         attributes, sourceURL, project);
+            }
+            else if (qualifiedName.equals("target")) {
+                TargetHandler targetHandler 
+                    = new TargetHandler(getXMLReader(), this, getLocator(), attributes);
+                try {                    
+                    project.addTarget(targetHandler.getTarget());
+                }
+                catch (ProjectModelException e) {
+                    throw new SAXParseException(e.getMessage(), getLocator(), e);
+                }
+            }
+            else {
+                // everything else is a task
+                TaskHandler taskHandler 
+                    = new TaskHandler(getXMLReader(), this, getLocator(), 
+                                      attributes, qualifiedName);
+                project.addTask(taskHandler.getTask());
+            }
+        }
+    
+        /**
+         * Get the project that has been parsed from the XML source
+         *
+         * @return the project model of the parsed project.
+         */
+        public Project getProject() {
+            return project;
+        }
+    }
+    
+    /**
+     * The import handler handles the importing of one project into another.
+     * 
+     * The project to be imported is parsed with a new parser and then added to the
+     * current project under the given import name
+     */
+    private class ImportHandler extends ElementHandler {
+        /**
+         * The attribute used to name the import.
+         */
+        static public final String IMPORT_NAME_ATTR = "name";
+        
+        /**
+         * The attribute name used to locate the project to be imported.
+         */
+        static public final String IMPORT_SYSTEMID_ATTR = "project";
+        
+        /**
+         * The project that has been imported.
+         */
+        private Project importedProject;
+        
+        /**
+         * The name under which the project is being imported.
+         */
+        private String importName;
+        
+        /**
+         * The systemId (URL) where the project is to be imported from.
+         */
+        private String projectSystemId;
+
+        /**
+         * Create an import handler to import a project.
+         *
+         * @param xmlReader the XML parser being used to parse the import element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes attributes of the import statement.
+         * @param importingSource the URL of the importing source.
+         */
+        public ImportHandler(XMLReader xmlReader, ContentHandler parent,
+                             Locator locator, Attributes attributes, URL importingSource) 
+                throws SAXParseException {
+            super(xmlReader, parent, locator);
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.equals(IMPORT_NAME_ATTR)) {
+                    importName = attributeValue;
+                }
+                else if (attributeName.equals(IMPORT_SYSTEMID_ATTR)) {
+                    projectSystemId = attributeValue;
+                }
+                else {
+                    throw new SAXParseException("Attribute " + attributeName + 
+                                                " is not allowed in an <import> element", getLocator());
+                }                                                    
+            }
+            
+            if (importName == null) {
+                throw new SAXParseException("Attribute " + IMPORT_NAME_ATTR + 
+                                            " is required in an <import> element", getLocator());
+            }
+            
+            if (projectSystemId == null) {
+                throw new SAXParseException("Attribute " + IMPORT_SYSTEMID_ATTR + 
+                                            " is required in an <import> element", getLocator());
+            }
+
+            // create a new parser to read this project relative to the 
+            // project's URI
+            try {
+                URL importURL = new URL(importingSource, projectSystemId);
+                SAXParser importSAXParser = parserFactory.newSAXParser();
+                XMLReader importXMLReader = importSAXParser.getXMLReader();
+    
+                
+                if (recursionCheck.contains(importURL)) {
+                    throw new SAXParseException("Circular import detected when importing '" + 
+                                                importURL + "'", getLocator());
+                }
+                recursionCheck.push(importURL);                                                
+                ProjectRootHandler importRootHandler = new ProjectRootHandler(importURL, importXMLReader);
+                importSAXParser.parse(importURL.toString(), importRootHandler);
+                if (recursionCheck.pop() != importURL) {
+                    throw new RuntimeException("Failure to pop expected element off recursion stack");
+                }
+                importedProject = importRootHandler.getProject();
+            }
+            catch (SAXParseException e) {
+                throw e;
+            }
+            catch (NoProjectReadException e) {
+                throw new SAXParseException("No project was imported from " + projectSystemId, 
+                                            getLocator());
+            }
+            catch (MalformedURLException e) {
+                throw new SAXParseException("Unable to import project from " + projectSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (ParserConfigurationException e) {
+                throw new SAXParseException("Unable to parse project imported from " + projectSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (SAXException e) {
+                throw new SAXParseException("Unable to parse project imported from " + projectSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (IOException e) {
+                throw new SAXParseException("Error reading project imported from " + projectSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+        }
+        
+        /**
+         * Import does not support nested elements. This method will always throw an
+         * exception
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException always.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            // everything is a task
+            throw new SAXParseException("<import> does not support nested elements", getLocator()); 
+        }
+        
+        /**
+         * Get the project imported.
+         *
+         * @return an imported Project.
+         */
+        public Project getImportedProject() {
+            return importedProject;
+        }
+        
+        /**
+         * Get the name under which the project is imported.
+         *
+         * @return the import name of the project
+         */
+        public String getImportName() {
+            return importName;
+        }
+    }
+
+    /**
+     * The include handler is used to read in included projects or
+     * fragments into a project.
+     */
+    private class IncludeHandler extends ElementHandler {
+        /**
+         * The attribute name which identifies the fragment to be included
+         */
+        static public final String INCLUDE_SYSTEMID_ATTR = "fragment";
+        
+        /**
+         * The system id of the fragment to be included.
+         */
+        private String includeSystemId;
+
+        /**
+         * Create an IncludeHandler to include an element into the
+         * current project
+         *       
+         * @param xmlReader the XML parser being used to parse the include element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes attributes of the include statement.
+         * @param includingSource the URL of the including source.
+         * @param project the project into which the included elements are added.
+         */
+        public IncludeHandler(XMLReader xmlReader, ContentHandler parent,
+                              Locator locator, Attributes attributes, URL includingSource,
+                              Project project) 
+                throws SAXParseException {
+            super(xmlReader, parent, locator);
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.equals(INCLUDE_SYSTEMID_ATTR)) {
+                    includeSystemId = attributeValue;
+                }
+                else {
+                    throw new SAXParseException("Attribute " + attributeName + 
+                                                " is not allowed in an <include> element", getLocator());
+                }                                                    
+            }
+            
+            if (includeSystemId == null) {
+                throw new SAXParseException("Attribute " + INCLUDE_SYSTEMID_ATTR + 
+                                            " is required in an <include> element", getLocator());
+            }
+
+            // create a new parser to read this project relative to the 
+            // project's URI
+            try {
+                URL includeURL = new URL(includingSource, includeSystemId);
+                SAXParser includeSAXParser = parserFactory.newSAXParser();
+                XMLReader includeXMLReader = includeSAXParser.getXMLReader();
+    
+                if (recursionCheck.contains(includeURL)) {
+                    throw new SAXParseException("Circular include detected when including '" + 
+                                                includeURL + "'", getLocator());
+                }
+                recursionCheck.push(includeURL);                                                
+                IncludeRootHandler includeRootHandler 
+                    = new IncludeRootHandler(includeURL, includeXMLReader, project);
+                includeSAXParser.parse(includeURL.toString(), includeRootHandler);
+                if (recursionCheck.pop() != includeURL) {
+                    throw new RuntimeException("Failure to pop expected element off recursion stack");
+                }
+            }
+            catch (SAXParseException e) {
+                throw e;
+            }
+            catch (MalformedURLException e) {
+                throw new SAXParseException("Unable to include " + includeSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (ParserConfigurationException e) {
+                throw new SAXParseException("Unable to parse include " + includeSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (SAXException e) {
+                throw new SAXParseException("Unable to parse include " + includeSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+            catch (IOException e) {
+                throw new SAXParseException("Error reading include " + includeSystemId + 
+                                            ": " + e.getMessage(), 
+                                            getLocator());
+            }
+        }
+
+        /**
+         * Include does not support nested elements. This method will always throw an
+         * exception
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException always.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            // everything is a task
+            throw new SAXParseException("<include> does not support nested elements", getLocator()); 
+        }
+        
+    }
+
+    /**
+     * A TargetHandler process the Target element.
+     */
+    private class TargetHandler extends ElementHandler {
+        /**
+         * The target being configured.
+         */
+        private Target target;
+        
+        /**
+         * Create a Target handler. Event element in a target is 
+         * considered to be a task
+         *
+         * @param xmlReader the XML parser being used to parse the target element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes attributes of the target
+         */
+        public TargetHandler(XMLReader xmlReader, ContentHandler parent,
+                             Locator locator, Attributes attributes) 
+                throws SAXParseException {
+            super(xmlReader, parent, locator);
+            String targetName = null;
+            String depends = null;
+            Map aspects = new HashMap();
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.equals("name")) {
+                    targetName = attributeValue;
+                }
+                else if (attributeName.equals("depends")) {
+                    depends = attributeValue;
+                }
+                else if (attributeName.indexOf(":") != -1) {
+                    // potential aspect attribute
+                    aspects.put(attributeName, attributeValue);
+                }
+                else {
+                    throw new SAXParseException("The attribute '" + attributeName + "' is not " + 
+                                                "supported by the <target> element", getLocator());
+                }
+            }
+            if (targetName == null) {
+                throw new SAXParseException("Targets must have a name attribute", locator);
+            }
+            target = new Target(getLocation(locator), targetName);
+            target.setAspects(aspects);
+            
+            if (depends != null) {
+                StringTokenizer tokenizer = new StringTokenizer(depends, ",");
+                while (tokenizer.hasMoreTokens()) {
+                    String dependency = tokenizer.nextToken();
+                    target.addDependency(dependency);
+                }
+            }
+        }
+
+        /*
+         * Process an element within this target. All elements within the target are 
+         * treated as tasks.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            // everything is a task
+            TaskHandler taskHandler 
+                = new TaskHandler(getXMLReader(), this, getLocator(), 
+                                  attributes, qualifiedName);
+            target.addTask(taskHandler.getTask());
+        }
+        
+        /**
+         * Get the target parsed by this handler.
+         *
+         * @return the Target model object parsed by this handler.
+         */
+        public Target getTarget() {
+            return target;
+        }
+    }
+
+    /**
+     * A Task Handler is used to parse tasks.
+     */
+    private class TaskHandler extends ElementHandler  {
+        /**
+         * The task being parsed by this handler.
+         */
+        private Task task;
+        
+        /**
+         * Create a task handler to parse the Task element
+         *
+         * @param xmlReader the XML parser being used to parse the task element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes attributes of the task
+         * @param taskTagName the name of the task.
+         */
+        public TaskHandler(XMLReader xmlReader, ContentHandler parent, Locator locator, 
+                           Attributes attributes, String taskTagName) {
+            super(xmlReader, parent, locator);     
+            task = new Task(getLocation(locator), taskTagName);
+            
+            Map aspects = new HashMap();
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.indexOf(":") != -1) {
+                    // potential aspect attribute
+                    aspects.put(attributeName, attributeValue);
+                }
+                else {
+                    task.addAttribute(attributeName, attributeValue);
+                }
+            }
+            task.setAspects(aspects);
+        }
+        
+        /*
+         * Process a nested element within this task. All nested elements within 
+         * the task are treated as taskelements.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            // everything within a task is a task element
+            TaskElementHandler taskElementHandler 
+                = new TaskElementHandler(getXMLReader(), this, getLocator(), 
+                                         attributes, qualifiedName);
+            task.addTaskElement(taskElementHandler.getTaskElement());                                         
+        }
+        
+        public void characters(char[] buf, int start, int end) throws SAXParseException {
+            task.addText(new String(buf, start, end));
+        }
+
+        /**
+         * Get the task that is being parsed
+         *
+         * @return the task being parsed by this task handler.
+         */
+        public Task getTask() {
+            return task;
+        }
+    }
+    
+    /**
+     * A Task Element Handler parses the nested elements of tasks.
+     */
+    private class TaskElementHandler extends ElementHandler  {
+        /**
+         * The task element being parsed by this handler.
+         */
+        private TaskElement taskElement;
+        
+        /**
+         * Create a task element handler to parse a task element
+         *
+         * @param xmlReader the XML parser being used to parse the task element.
+         * @param parent the parent element handler.
+         * @param locator the SAX locator object used to associate elements with source
+         *        locations.
+         * @param attributes attributes of the task element
+         * @param elementTagName the name of the task element.
+         */
+        public TaskElementHandler(XMLReader xmlReader, ContentHandler parent, Locator locator, 
+                                  Attributes attributes, String elementTagName) {
+            super(xmlReader, parent, locator);     
+            taskElement 
+                = new TaskElement(getLocation(locator), elementTagName);
+                
+            Map aspects = new HashMap();
+            for (int i = 0; i < attributes.getLength(); ++i) {
+                String attributeName = attributes.getQName(i);
+                String attributeValue = attributes.getValue(i);
+                if (attributeName.indexOf(":") != -1) {
+                    // potential aspect attribute
+                    aspects.put(attributeName, attributeValue);
+                }
+                else {
+                    taskElement.addAttribute(attributeName, attributeValue);
+                }
+            }
+            taskElement.setAspects(aspects);
+        }
+        
+        /** 
+         * Process a nested element of this task element. All nested elements
+         * of a taskElement are themselves taskElements.
+         *
+         * @param uri The Namespace URI.
+         * @param localName The local name (without prefix).
+         * @param qualifiedName The qualified name (with prefix)
+         * @param attributes The attributes attached to the element. 
+         *
+         * @throws SAXParseException if there is a parsing problem.
+         */
+        public void startElement(String uri, String localName, String qualifiedName,
+                                 Attributes attributes) throws SAXParseException {
+            // everything within a task element is also a task element
+            TaskElementHandler taskElementHandler 
+                = new TaskElementHandler(getXMLReader(), this, getLocator(), 
+                                         attributes, qualifiedName);
+            taskElement.addTaskElement(taskElementHandler.getTaskElement());                                         
+        }
+        
+        public void characters(char[] buf, int start, int end) throws SAXParseException {
+            taskElement.addText(new String(buf, start, end));
+        }
+
+        /**
+         * Get the task element being parsed by this handler.
+         *
+         * @return the TaskElement being parsed.
+         */
+        public TaskElement getTaskElement() {
+            return taskElement;
+        }
+    }
+    
+    /**
+     * A NoProjectReadException is used to indicate that a project
+     * was not read from the particular source. This will happen
+     * if the source is empty.
+     */
+    private class NoProjectReadException extends Exception {
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/frontend/BuildLogger.java

@@ -0,0 +1,94 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import org.apache.ant.core.execution.*;
+
+import java.io.*;
+
+/**
+ * Interface used by Ant to log the build output. 
+ *
+ * A build logger is a build listener which has the 'right' to send output to the
+ * ant log, which is usually System.out unles redirected by the -logfile option.
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */
+public interface BuildLogger extends BuildListener {
+    /**
+     * Set the msgOutputLevel this logger is to respond to.
+     *
+     * Only messages with a message level lower than or equal to the given level are 
+     * output to the log.
+     *
+     * @param level the logging level for the logger.
+     */
+    public void setMessageOutputLevel(int level);
+    
+    /**
+     * Set the output stream to which this logger is to send its output.
+     *
+     * @param output the output stream for the logger.
+     */
+    public void setOutputPrintStream(PrintStream output);
+    
+    /**
+     * Set the output stream to which this logger is to send error messages.
+     *
+     * @param err the error stream for the logger.
+     */
+    public void setErrorPrintStream(PrintStream err);
+    
+}

proposal/mutant/src/main/org/apache/ant/frontend/Commandline.java

@@ -0,0 +1,307 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import java.io.*;
+import java.net.*;
+import java.util.*;
+import javax.xml.parsers.*;
+import org.xml.sax.SAXParseException;
+import java.lang.reflect.*;
+
+import org.apache.ant.core.execution.*;
+import org.apache.ant.core.support.*;
+import org.apache.ant.core.xml.*;
+import org.apache.ant.core.config.*;
+import org.apache.ant.core.model.*;
+
+/**
+ * This is the command line front end to end. It drives the core
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Commandline {
+    /** The default build file name */
+    static public final String DEFAULT_BUILD_FILENAME = "build.ant";
+
+    /** Stream that we are using for logging */
+    private PrintStream out = System.out;
+
+    /** Stream that we are using for logging error messages */
+    private PrintStream err = System.err;
+
+    /** Names of classes to add as listeners to project */
+    private List listeners = new ArrayList(2);
+
+    /** The list of targets to be evaluated in this invocation */
+    private List targets = new ArrayList(4);
+
+    /** Our current message output status. Follows Project.MSG_XXX */
+    private int messageOutputLevel = BuildEvent.MSG_VERBOSE;
+
+    /**
+     * This is the build file to run. By default it is a file: type URL
+     * but other URL protocols can be used.
+     */
+    private URL buildFileURL;
+    
+    /**
+     * The Ant logger class. There may be only one logger. It will have the
+     * right to use the 'out' PrintStream. The class must implements the BuildLogger
+     * interface
+     */
+    private String loggerClassname = null;
+
+    public static void start(String[] args) {
+        // create a command line and use it to run ant
+        Commandline commandline = new Commandline();
+        commandline.runAnt(args);
+    }
+    
+    public void runAnt(String[] args) {
+        ExecutionManager executionManager = null;
+        try {
+            parseArguments(args);
+            Project project = getProject();
+            for (Iterator i = project.getTargets(); i.hasNext();) {
+                Target target = (Target)i.next();
+            }
+
+            // Get the list of library components 
+            AntLibrary[] libraries = ComponentManager.getComponents();
+            executionManager = new ExecutionManager();
+            executionManager.addLibraries(libraries);
+            executionManager.setProject(project);
+            addBuildListeners(executionManager);
+        }
+        catch (AntException e) {
+            Location location = e.getLocation();
+            Throwable cause = e.getCause();
+            if (location != null && location != Location.UNKNOWN_LOCATION) {
+                System.out.print(location);
+            }
+            System.out.print(e.getMessage());
+            
+            if (cause != null) {
+                System.out.println();
+                System.out.print("Root cause: " + cause.getClass().getName() + ": " + cause.getMessage());
+            }
+            System.out.println();
+            
+            System.exit(1);
+        }
+        
+        try {
+            executionManager.runBuild(targets);
+            System.exit(0);
+        }
+        catch (Exception e) {
+            System.exit(1);
+        }
+    }
+    
+    protected void addBuildListeners(ExecutionManager executionManager) 
+            throws ConfigException {
+
+        // Add the default listener
+        executionManager.addBuildListener(createLogger());
+
+        for (Iterator i = listeners.iterator(); i.hasNext(); ) {
+            String className = (String) i.next();
+            try {
+                BuildListener listener =
+                    (BuildListener) Class.forName(className).newInstance();
+                executionManager.addBuildListener(listener);
+            }
+            catch(Exception exc) {
+                throw new ConfigException("Unable to instantiate listener " + className, exc);
+            }
+        }
+    }
+    
+    /**
+     *  Creates the default build logger for sending build events to the ant log.
+     */
+    private BuildLogger createLogger() throws ConfigException {
+        BuildLogger logger = null;
+        if (loggerClassname != null) {
+            try {
+                logger = (BuildLogger)(Class.forName(loggerClassname).newInstance());
+            }
+            catch (ClassCastException e) {
+                System.err.println("The specified logger class " + loggerClassname +
+                                         " does not implement the BuildLogger interface");
+                throw new ConfigException("Unable to instantiate logger " + loggerClassname, e);
+            }
+            catch (Exception e) {
+                System.err.println("Unable to instantiate specified logger class " +
+                                           loggerClassname + " : " + e.getClass().getName());
+                throw new ConfigException("Unable to instantiate logger " + loggerClassname, e);
+            }
+        }
+        else {
+            logger = new DefaultLogger();
+        }
+
+        logger.setMessageOutputLevel(messageOutputLevel);
+        logger.setOutputPrintStream(out);
+        logger.setErrorPrintStream(err);
+
+        return logger;
+    }
+
+
+    /**
+     * Parse the command line arguments.
+     */
+    private void parseArguments(String[] args) throws ConfigException {
+        for (int i = 0; i < args.length; i++) {
+            String arg = args[i];
+
+            if (arg.equals("-buildfile") || arg.equals("-file") || arg.equals("-f")) {
+                try {
+                    String url = args[i+1];
+                    if (url.indexOf(":") == -1) {
+                        File file = new File(url);
+                        String uri = "file:" + file.getAbsolutePath().replace('\\', '/');
+                        for (int index = uri.indexOf('#'); index != -1; index = uri.indexOf('#')) {
+                            uri = uri.substring(0, index) + "%23" + uri.substring(index+1);
+                        }
+                        buildFileURL = new URL(uri);
+                        // We convert any hash characters to their URL escape.
+                    }
+                    else {
+                        buildFileURL = new URL(url);
+                    }
+                    i++;
+                }
+                catch (MalformedURLException e) {
+                    System.err.println("Buildfile is not valid: " + e.getMessage());
+                    throw new ConfigException("Build file is not valid", e);
+                } 
+                catch (ArrayIndexOutOfBoundsException e) {
+                    System.err.println("You must specify a buildfile when " +
+                                       "using the -buildfile argument");
+                    return;
+                }
+            }
+            else if (arg.equals("-logfile") || arg.equals("-l")) {
+                try {
+                    File logFile = new File(args[i+1]);
+                    i++;
+                    out = new PrintStream(new FileOutputStream(logFile));
+                    err = out;
+                } catch (IOException ioe) {
+                    System.err.println("Cannot write on the specified log file. " +
+                                       "Make sure the path exists and you have write permissions.");
+                    return;
+                } catch (ArrayIndexOutOfBoundsException aioobe) {
+                    System.err.println("You must specify a log file when " +
+                                       "using the -log argument");
+                    return;
+                }
+            }
+            else if (arg.equals("-listener")) {
+                try {
+                    listeners.add(args[i+1]);
+                    i++;
+                } catch (ArrayIndexOutOfBoundsException aioobe) {
+                    System.err.println("You must specify a classname when " +
+                                       "using the -listener argument");
+                    return;
+                }
+            } 
+            else if (arg.equals("-logger")) {
+                if (loggerClassname != null) {
+                    System.err.println("Only one logger class may be specified.");
+                    return;
+                }
+                try {
+                    loggerClassname = args[++i];
+                } catch (ArrayIndexOutOfBoundsException aioobe) {
+                    System.err.println("You must specify a classname when " +
+                                       "using the -logger argument");
+                    return;
+                }
+            }
+            else if (arg.startsWith("-")) {
+                // we don't have any more args to recognize!
+                System.out.println("Unknown argument: " + arg);
+                return;
+            } else {
+                // if it's no other arg, it must be a target
+                targets.add(arg);
+            }
+        }
+        
+        if (buildFileURL == null) {
+            File defaultBuildFile = new File(DEFAULT_BUILD_FILENAME);
+            try {
+                buildFileURL = defaultBuildFile.toURL();
+            }
+            catch (MalformedURLException e) {
+                System.err.println("Buildfile is not valid: " + e.getMessage());
+                throw new ConfigException("Build file is not valid", e);
+            } 
+        }
+    }
+    
+    private Project getProject() throws ConfigException {
+        XMLProjectParser parser = new XMLProjectParser();
+        Project project = parser.parseBuildFile(buildFileURL); 
+        return project;       
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/frontend/DefaultLogger.java

@@ -0,0 +1,227 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 1999 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import org.apache.ant.core.support.*;
+import org.apache.ant.core.model.*;
+import org.apache.ant.core.execution.*;
+import java.io.*;
+
+/**
+ *  Writes build event to a PrintStream. Currently, it
+ *  only writes which targets are being executed, and
+ *  any messages that get logged.
+ */
+public class DefaultLogger implements BuildLogger {
+    private static int LEFT_COLUMN_SIZE = 12;
+
+    protected PrintStream out;
+    protected PrintStream err;
+    protected int msgOutputLevel = BuildEvent.MSG_ERR;
+    private long startTime = System.currentTimeMillis();
+
+    protected static String lSep = System.getProperty("line.separator");
+
+    protected boolean emacsMode = false;
+
+    /**
+     * Set the msgOutputLevel this logger is to respond to.
+     *
+     * Only messages with a message level lower than or equal to the given level are 
+     * output to the log.
+     * <P>
+     * Constants for the message levels are in Project.java. The order of
+     * the levels, from least to most verbose, is MSG_ERR, MSG_WARN,
+     * MSG_INFO, MSG_VERBOSE, MSG_DEBUG.
+     *
+     * The default message level for DefaultLogger is Project.MSG_ERR.
+     *
+     * @param level the logging level for the logger.
+     */
+    public void setMessageOutputLevel(int level) {
+        this.msgOutputLevel = level;
+    }
+
+    
+    /**
+     * Set the output stream to which this logger is to send its output.
+     *
+     * @param output the output stream for the logger.
+     */
+    public void setOutputPrintStream(PrintStream output) {
+        this.out = output;
+    }
+
+    /**
+     * Set the output stream to which this logger is to send error messages.
+     *
+     * @param err the error stream for the logger.
+     */
+    public void setErrorPrintStream(PrintStream err) {
+        this.err = err;
+    }
+
+    /**
+     * Set this logger to produce emacs (and other editor) friendly output.
+     *
+     * @param emacsMode true if output is to be unadorned so that emacs and other
+     * editors can parse files names, etc.
+     */
+    public void setEmacsMode(boolean emacsMode) {
+        this.emacsMode = emacsMode;
+    }
+
+    public void reportException(Throwable t) {
+        if (t instanceof AntException) {
+            AntException e = (AntException)t;
+            Location location = e.getLocation();
+            Throwable cause = e.getCause();
+            if (location != null && location != Location.UNKNOWN_LOCATION) {
+                out.print(location);
+            }
+            out.print(e.getMessage());
+            
+            if (cause != null) {
+                out.println();
+                out.print("Root cause: " + cause.getClass().getName() + ": " + cause.getMessage());
+            }
+            out.println();
+        }
+        else {
+            t.printStackTrace(err);
+        }
+    }
+    
+    public void processBuildEvent(BuildEvent event) {
+        switch (event.getEventType()) {
+            case BuildEvent.BUILD_STARTED:
+                startTime = System.currentTimeMillis();
+                break;
+            case BuildEvent.BUILD_FINISHED:
+                Throwable cause = event.getCause();
+        
+                if (cause == null) {
+                    out.println(lSep + "BUILD SUCCESSFUL");
+                }
+                else {
+                    err.println(lSep + "BUILD FAILED" + lSep);
+        
+                    reportException(cause);
+                }
+        
+                out.println(lSep + "Total time: " + formatTime(System.currentTimeMillis() - startTime));
+                break;
+            case BuildEvent.TARGET_STARTED:
+                if (BuildEvent.MSG_INFO <= msgOutputLevel) {
+                    Target target = (Target)event.getBuildElement();
+                    out.println(lSep + target.getName() + ":");
+                }
+                break;
+            case BuildEvent.TARGET_FINISHED:
+                break;
+            case BuildEvent.TASK_STARTED:
+                break;
+            case BuildEvent.TASK_FINISHED:
+                break;
+            case BuildEvent.MESSAGE:
+                PrintStream logTo = event.getPriority() == BuildEvent.MSG_ERR ? err : out;
+        
+                // Filter out messages based on priority
+                if (event.getPriority() <= msgOutputLevel) {
+        
+                    // Print out the name of the task if we're in one
+                    Object buildElement = event.getBuildElement();
+                    if (buildElement instanceof Task) {
+                        Task task = (Task)buildElement;
+                        String name = task.getType();
+        
+                        if (!emacsMode) {
+                            String msg = "[" + name + "] ";
+                            for (int i = 0; i < (LEFT_COLUMN_SIZE - msg.length()); i++) {
+                                logTo.print(" ");
+                            }
+                            logTo.print(msg);
+                        }
+                    }
+        
+                    // Print the message
+                    logTo.println(event.getMessage());
+                }
+                break;
+            default:
+                err.println("Unrecognized event type = " + event.getEventType());
+                break;
+        }
+    }            
+
+    protected static String formatTime(long millis) {
+        long seconds = millis / 1000;
+        long minutes = seconds / 60;
+
+
+        if (minutes > 0) {
+            return Long.toString(minutes) + " minute"
+                + (minutes == 1 ? " " : "s ")
+                + Long.toString(seconds%60) + " second"
+                + (seconds%60 == 1 ? "" : "s");
+        }
+        else {
+            return Long.toString(seconds) + " second"
+                + (seconds%60 == 1 ? "" : "s");
+        }
+
+    }
+
+}

proposal/mutant/src/main/org/apache/ant/frontend/EmbedTest.java

@@ -0,0 +1,77 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import java.io.*;
+import java.net.*;
+import java.util.*;
+import javax.xml.parsers.*;
+import org.xml.sax.SAXParseException;
+import java.lang.reflect.*;
+
+import org.apache.ant.core.support.*;
+import org.apache.ant.core.xml.*;
+import org.apache.ant.core.config.*;
+
+/**
+ * This class illustrates the use of the ExecutionFrame class
+ * standalone to execute tasks
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class EmbedTest {
+    
+}
+

proposal/mutant/src/main/org/apache/ant/frontend/Launcher.java

@@ -0,0 +1,89 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import java.io.*;
+import java.net.*;
+import javax.xml.parsers.*;
+import java.lang.reflect.*;
+
+import org.apache.ant.core.support.*;
+
+/**
+ * This is the command line front end to end. It drives the core
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class Launcher {
+    public static void main(String[] args) throws Exception {
+        
+        // we need to find the parser jars and makre sure we are going to use
+        // those in preference to anything else that may be lying about in the
+        // user's classpath
+        AntClassLoader coreClassLoader = AntLocator.getCoreClassLoader(System.getProperties());
+
+        URL frontEndURL = AntLocator.getClassLocationURL(Launcher.class);
+        coreClassLoader.addURL(frontEndURL);
+        
+        Class commandLineClass = Class.forName("org.apache.ant.frontend.Commandline", true, coreClassLoader);
+        
+        final Class[] param = {Class.forName("[Ljava.lang.String;")};
+        Class target = null;
+        final Method startMethod = commandLineClass.getMethod("start", param);
+        final Object[] argument = {args};
+        startMethod.invoke(null, argument);
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/frontend/RemoteLauncher.java

@@ -0,0 +1,97 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Ant", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.ant.frontend;
+
+import java.io.*;
+import java.net.*;
+import javax.xml.parsers.*;
+import java.lang.reflect.*;
+
+import org.apache.ant.core.support.*;
+
+/**
+ * Command line to run Ant core from a remote server
+ *
+ * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
+ */ 
+public class RemoteLauncher {
+    public static void main(String[] args) throws Exception {
+
+        String antHome = args[0];
+        String parserHome = args[1];
+        
+        URL[] remoteCore = new URL[3];
+        remoteCore[0] = new URL(antHome + "/lib/core.jar");
+        remoteCore[1] = new URL(antHome + "/lib/frontend.jar");
+        remoteCore[2] = new URL(parserHome);
+        AntClassLoader coreClassLoader = new AntClassLoader(remoteCore);
+
+        String[] realArgs = new String[args.length - 2];
+        System.arraycopy(args, 2, realArgs, 0, realArgs.length);
+                
+
+        System.out.print("Loading remote Ant ... ");        
+        Class launcher = Class.forName("org.apache.ant.frontend.Commandline", true, coreClassLoader);
+        
+        final Class[] param = { Class.forName("[Ljava.lang.String;") };
+        Class target = null;
+        final Method startMethod = launcher.getMethod("start", param);
+        final Object[] argument = {realArgs};
+        System.out.println("Done");        
+        System.out.println("Starting remote Ant");        
+        startMethod.invoke(null, argument);
+    }
+}
+

proposal/mutant/src/main/org/apache/ant/frontend/eggmanifest.mf

@@ -0,0 +1,5 @@
+Manifest-Version: 1.0
+Created-By: Ant 2.0alpha
+Main-Class: org.apache.ant.frontend.RemoteLauncher
+Class-Path: core.jar
+Sealed: true

proposal/mutant/src/main/org/apache/ant/frontend/manifest.mf

@@ -0,0 +1,5 @@
+Manifest-Version: 1.0
+Created-By: Ant 2.0alpha
+Main-Class: org.apache.ant.frontend.Launcher
+Class-Path: core.jar
+Sealed: true