Add a simple buildnumber task.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271960 13f79535-47bb-0310-9956-ffa450edef68

proposal/myrmidon/src/java/org/apache/antlib/build/BuildNumber.java

@@ -0,0 +1,200 @@
+/*
+ * Copyright (C) The Apache Software Foundation. All rights reserved.
+ *
+ * This software is published under the terms of the Apache Software License
+ * version 1.1, a copy of which has been included  with this distribution in
+ * the LICENSE.txt file.
+ */
+package org.apache.antlib.build;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.Properties;
+import org.apache.avalon.excalibur.i18n.ResourceManager;
+import org.apache.avalon.excalibur.i18n.Resources;
+import org.apache.avalon.excalibur.io.IOUtil;
+import org.apache.myrmidon.api.AbstractTask;
+import org.apache.myrmidon.api.TaskException;
+
+/**
+ * This is a basic task that can be used to track build numbers.
+ *
+ * It will first attempt to read a build number from a file, then
+ * set the property "build.number" to the value that was read in
+ * (or 0 if no such value). Then it will increment the build number
+ * by one and write it back out into the file.
+ *
+ * @author <a href="mailto:peter@apache.org">Peter Donald</a>
+ * @version $Revision$ $Date$
+ * @ant:task name="build-number"
+ */
+public class BuildNumber
+    extends AbstractTask
+{
+    private final static Resources REZ =
+        ResourceManager.getPackageResources( BuildNumber.class );
+
+    /**
+     * The name of the property in which the build number is stored.
+     */
+    private static final String DEFAULT_PROPRTY_NAME = "build.number";
+
+    /**
+     * The default filename to use if no file specified.
+     */
+    private static final String DEFAULT_FILENAME = DEFAULT_PROPRTY_NAME;
+
+    /**
+     * The File in which the build number is stored.
+     */
+    private File m_file;
+
+    /**
+     * Specify the file in which the build numberis stored.
+     * Defaults to "build.number" if not specified.
+     *
+     * @param file the file in which build number is stored.
+     */
+    public void setFile( final File file )
+    {
+        m_file = file;
+    }
+
+    /**
+     * Run task.
+     *
+     * @exception TaskException if an error occurs
+     */
+    public void execute()
+        throws TaskException
+    {
+        validate();
+
+        final Properties properties = loadProperties();
+        final int buildNumber = getBuildNumber( properties );
+
+        properties.put( DEFAULT_PROPRTY_NAME,
+                        String.valueOf( buildNumber + 1 ) );
+
+        // Write the properties file back out
+        FileOutputStream output = null;
+        try
+        {
+            final String header = REZ.getString( "buildnumber.header.info" );
+
+            output = new FileOutputStream( m_file );
+            properties.store( output, header );
+        }
+        catch( final IOException ioe )
+        {
+            final String message =
+                REZ.getString( "buildnumber.badwrite.error", m_file );
+            throw new TaskException( message, ioe );
+        }
+        finally
+        {
+            IOUtil.shutdownStream( output );
+        }
+
+        //Finally set the property
+        getContext().setProperty( DEFAULT_PROPRTY_NAME,
+                                  String.valueOf( buildNumber ) );
+    }
+
+    /**
+     * Utility method to retrieve build number from properties object.
+     *
+     * @param properties the properties to retrieve build number from
+     * @return the build number or if no number in properties object
+     * @throws TaskException if build.number property is not an integer
+     */
+    private int getBuildNumber( final Properties properties )
+        throws TaskException
+    {
+        final String buildNumber =
+            properties.getProperty( DEFAULT_PROPRTY_NAME, "0" ).trim();
+
+        // Try parsing the line into an integer.
+        try
+        {
+            return Integer.parseInt( buildNumber );
+        }
+        catch( final NumberFormatException nfe )
+        {
+            final String message =
+                REZ.getString( "buildnumber.noparse.error", m_file, buildNumber );
+            throw new TaskException( message, nfe );
+        }
+    }
+
+    /**
+     * Utility method to load properties from file.
+     *
+     * @return the loaded properties
+     * @throws TaskException
+     */
+    private Properties loadProperties()
+        throws TaskException
+    {
+        FileInputStream input = null;
+        try
+        {
+            final Properties properties = new Properties();
+            input = new FileInputStream( m_file );
+            properties.load( input );
+            return properties;
+        }
+        catch( final IOException ioe )
+        {
+            throw new TaskException( ioe.getMessage(), ioe );
+        }
+        finally
+        {
+            IOUtil.shutdownStream( input );
+        }
+    }
+
+    /**
+     * Validate that the task parameters are valid.
+     *
+     * @throws TaskException if parameters are invalid
+     */
+    private void validate()
+        throws TaskException
+    {
+        if( null == m_file )
+        {
+            m_file = getContext().resolveFile( DEFAULT_FILENAME );
+        }
+
+        if( !m_file.exists() )
+        {
+            try
+            {
+                m_file.createNewFile();
+            }
+            catch( final IOException ioe )
+            {
+                final String message =
+                    REZ.getString( "buildnumber.nocreate.error", m_file );
+                throw new TaskException( message, ioe );
+            }
+        }
+
+        if( !m_file.canRead() )
+        {
+            final String message =
+                REZ.getString( "buildnumber.noread.error", m_file );
+            throw new TaskException( message );
+        }
+
+        if( !m_file.canWrite() )
+        {
+            final String message =
+                REZ.getString( "buildnumber.nowrite.error", m_file );
+            throw new TaskException( message );
+        }
+    }
+}

proposal/myrmidon/src/java/org/apache/antlib/build/Resources.properties

@@ -4,3 +4,10 @@ sleep.neg-time.error=Negative sleep periods are not supported.
 patch.missing-file.error=Patchfile argument is required.
 patch.file-noexist.error=Patchfile "{0}" doesn\'t exist.
 patch.neg-strip.error=Strip has to be >= 0
+
+buildnumber.nocreate.error={0} doesn't exist and new file can't be created.
+buildnumber.noread.error=Unable to read from {0}.
+buildnumber.nowrite.error=Unable to write to {0}.
+buildnumber.noparse.error={0} contains a non integer build number: {1}
+buildnumber.badwrite.error=Error while writing {0}.
+buildnumber.header.info=Build Number for ANT. Do not edit!