Replace need for Composable tasks with TaskContext.getService()

Submitted By: "Adam Murdoch" <adammurdoch_ml@yahoo.com>


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@270847 13f79535-47bb-0310-9956-ffa450edef68

proposal/myrmidon/src/java/org/apache/myrmidon/api/AbstractTask.java

@@ -8,9 +8,7 @@
 package org.apache.myrmidon.api;
 
 import java.io.File;
-import org.apache.avalon.framework.context.Context;
 import org.apache.avalon.framework.context.ContextException;
-import org.apache.avalon.framework.context.Contextualizable;
 import org.apache.avalon.framework.logger.AbstractLogEnabled;
 
 /**
@@ -31,6 +29,7 @@ public abstract class AbstractTask
      * @param context the context
      */
     public void contextualize( final TaskContext context )
+        throws TaskException
     {
         m_context = context;
     }
@@ -104,6 +103,12 @@ public abstract class AbstractTask
         getContext().setProperty( name, value, scope );
     }
 
+    protected final Object getService( final Class serviceClass )
+        throws TaskException
+    {
+        return getContext().getService( serviceClass );
+    }
+
     protected final TaskContext createSubContext( final String name )
         throws TaskException
     {

proposal/myrmidon/src/java/org/apache/myrmidon/api/Task.java

@@ -29,7 +29,8 @@ public interface Task
      * The Task will use the TaskContext to receive information
      * about it's environment.
      */
-    void contextualize( TaskContext context );
+    void contextualize( TaskContext context )
+        throws TaskException;
 
     /**
      * Execute task.

proposal/myrmidon/src/java/org/apache/myrmidon/components/executor/AspectAwareExecutor.java

@@ -81,9 +81,6 @@ public class AspectAwareExecutor
         debug( "contextualizing.notice" );
         doContextualize( task, taskModel, frame.getContext() );
 
-        debug( "composing.notice" );
-        doCompose( task, taskModel, frame.getComponentManager() );
-
         debug( "configuring.notice" );
         getAspectManager().preConfigure( taskModel );
         doConfigure( task, taskModel, frame.getContext() );

proposal/myrmidon/src/java/org/apache/myrmidon/components/executor/DefaultExecutionFrame.java

@@ -12,9 +12,11 @@ import org.apache.avalon.framework.component.ComponentManager;
 import org.apache.avalon.framework.component.Composable;
 import org.apache.avalon.framework.context.Context;
 import org.apache.avalon.framework.context.Contextualizable;
+import org.apache.avalon.framework.context.ContextException;
 import org.apache.avalon.framework.logger.LogEnabled;
 import org.apache.avalon.framework.logger.Logger;
 import org.apache.myrmidon.api.TaskContext;
+import org.apache.myrmidon.api.TaskException;
 import org.apache.myrmidon.interfaces.executor.ExecutionFrame;
 import org.apache.myrmidon.interfaces.type.TypeManager;
 
@@ -24,36 +26,28 @@ import org.apache.myrmidon.interfaces.type.TypeManager;
  * @author <a href="mailto:peter@apache.org">Peter Donald</a>
  */
 public class DefaultExecutionFrame
-    implements ExecutionFrame, LogEnabled, Contextualizable, Composable
+    implements ExecutionFrame, LogEnabled, Contextualizable
 {
-    private TypeManager m_typeManager;
-
     private Logger m_logger;
     private TaskContext m_context;
-    private ComponentManager m_componentManager;
+    private TypeManager m_typeManager;
 
     public void enableLogging( final Logger logger )
     {
         m_logger = logger;
     }
 
-    public void contextualize( final Context context )
+    public void contextualize( final Context context ) throws ContextException
     {
         m_context = (TaskContext)context;
-    }
-
-    /**
-     * Retrieve relevent services needed to deploy.
-     *
-     * @param componentManager the ComponentManager
-     * @exception ComponentException if an error occurs
-     */
-    public void compose( final ComponentManager componentManager )
-        throws ComponentException
-    {
-        m_componentManager = componentManager;
-
-        m_typeManager = (TypeManager)componentManager.lookup( TypeManager.ROLE );
+        try
+        {
+            m_typeManager = (TypeManager)m_context.getService( TypeManager.class );
+        }
+        catch( TaskException te )
+        {
+            throw new ContextException(te.getMessage(), te);
+        }
     }
 
     public TypeManager getTypeManager()
@@ -70,9 +64,4 @@ public class DefaultExecutionFrame
     {
         return m_context;
     }
-
-    public ComponentManager getComponentManager()
-    {
-        return m_componentManager;
-    }
 }

proposal/myrmidon/src/java/org/apache/myrmidon/components/executor/DefaultExecutor.java

@@ -61,9 +61,6 @@ public class DefaultExecutor
         debug( "contextualizing.notice" );
         doContextualize( task, taskModel, frame.getContext() );
 
-        debug( "composing.notice" );
-        doCompose( task, taskModel, frame.getComponentManager() );
-
         debug( "configuring.notice" );
         doConfigure( task, taskModel, frame.getContext() );
 
@@ -115,29 +112,6 @@ public class DefaultExecutor
         }
     }
 
-    protected final void doCompose( final Task task,
-                                    final Configuration taskModel,
-                                    final ComponentManager componentManager )
-        throws TaskException
-    {
-        if( task instanceof Composable )
-        {
-            try
-            {
-                ( (Composable)task ).compose( componentManager );
-            }
-            catch( final Throwable throwable )
-            {
-                final String message =
-                    REZ.getString( "compose.error",
-                                   taskModel.getName(),
-                                   taskModel.getLocation(),
-                                   throwable.getMessage() );
-                throw new TaskException( message, throwable );
-            }
-        }
-    }
-
     protected final void doContextualize( final Task task,
                                           final Configuration taskModel,
                                           final TaskContext context )

proposal/myrmidon/src/java/org/apache/myrmidon/components/executor/Resources.properties

@@ -1,7 +1,6 @@
 creating.notice=Creating.
 logger.notice=Setting Logger.
 contextualizing.notice=Contextualizing.
-composing.notice=Composing.
 configuring.notice=Configuring.
 initializing.notice=Initializing.
 executing.notice=Executing.
@@ -9,7 +8,6 @@ disposing.notice=Disposing.
 
 no-create.error=Unable to create task {0}.
 config.error=Error configuring task {0} at {1} (Reason: {2}).
-compose.error=Error composing task {0} at {1} (Reason: {2}).
 contextualize.error=Error contextualizing task {0} at {1} (Reason: {2}).
 dispose.error=Error disposing task {0} at {1} (Reason: {2}).
 init.error=Error initializing task {0} at {1} (Reason: {2}).

proposal/myrmidon/src/java/org/apache/myrmidon/components/workspace/DefaultTaskContext.java

@@ -8,12 +8,14 @@
 package org.apache.myrmidon.components.workspace;
 
 import java.io.File;
-import java.util.Map;
 import org.apache.avalon.excalibur.i18n.ResourceManager;
 import org.apache.avalon.excalibur.i18n.Resources;
 import org.apache.avalon.excalibur.io.FileUtil;
 import org.apache.avalon.excalibur.property.PropertyException;
 import org.apache.avalon.excalibur.property.PropertyUtil;
+import org.apache.avalon.framework.component.Component;
+import org.apache.avalon.framework.component.ComponentException;
+import org.apache.avalon.framework.component.ComponentManager;
 import org.apache.avalon.framework.context.ContextException;
 import org.apache.avalon.framework.context.DefaultContext;
 import org.apache.myrmidon.api.TaskContext;
@@ -31,32 +33,44 @@ public class DefaultTaskContext
     private final static Resources REZ =
         ResourceManager.getPackageResources( DefaultTaskContext.class );
 
+    private ComponentManager m_componentManager;
+
     /**
      * Constructor for Context with no parent contexts.
      */
-    public DefaultTaskContext( final Map contextData )
+    public DefaultTaskContext()
     {
-        super( contextData );
+        this( (TaskContext)null );
     }
 
     /**
-     * Constructor for Context with no parent contexts.
+     * Constructor that specified parent context.
      */
-    public DefaultTaskContext()
+    public DefaultTaskContext( final TaskContext parent )
     {
-        this( (TaskContext)null );
+        this( parent, null );
     }
 
     /**
-     * Constructor.
+     * Constructor that specifies the ComponentManager for context.
      */
-    public DefaultTaskContext( final TaskContext parent )
+    public DefaultTaskContext( final ComponentManager componentManager )
+    {
+        this( null, componentManager );
+    }
+
+    /**
+     * Constructor that takes both parent context and a service directory.
+     */
+    public DefaultTaskContext( final TaskContext parent,
+                               final ComponentManager componentManager )
     {
         super( parent );
+        m_componentManager = componentManager;
     }
 
     /**
-     * Retrieve Name of tasklet.
+     * Retrieve Name of task.
      *
      * @return the name
      */
@@ -104,7 +118,42 @@ public class DefaultTaskContext
     public Object getService( final Class serviceClass )
         throws TaskException
     {
-        throw new TaskException( "No services available atm" );
+        // Try this context first
+        final String name = serviceClass.getName();
+        if( m_componentManager.hasComponent( name ) )
+        {
+            try
+            {
+                final Component service = m_componentManager.lookup( name );
+                if( !serviceClass.isInstance( service ) )
+                {
+                    final String message =
+                        REZ.getString( "bad-service-class.error",
+                                       name,
+                                       service.getClass().getName(),
+                                       serviceClass.getName() );
+                    throw new TaskException( message );
+                }
+
+                return service;
+            }
+            catch( final ComponentException ce )
+            {
+                final String message = REZ.getString( "bad-find-service.error", name );
+                throw new TaskException( message, ce );
+            }
+        }
+
+        // Try parent
+        final TaskContext parent = (TaskContext)getParent();
+        if( null != parent )
+        {
+            return parent.getService( serviceClass );
+        }
+
+        // Not found
+        final String message = REZ.getString( "bad-find-service.error", name );
+        throw new TaskException( message );
     }
 
     /**
@@ -194,9 +243,11 @@ public class DefaultTaskContext
     {
         checkPropertyValid( name, value );
 
-        if( CURRENT == scope ) {
+        if( CURRENT == scope )
+        {
             put( name, value );
-        } else if( PARENT == scope )
+        }
+        else if( PARENT == scope )
         {
             if( null == getParent() )
             {

proposal/myrmidon/src/java/org/apache/myrmidon/components/workspace/DefaultWorkspace.java

@@ -19,7 +19,6 @@ import org.apache.avalon.framework.component.ComponentManager;
 import org.apache.avalon.framework.component.Composable;
 import org.apache.avalon.framework.component.DefaultComponentManager;
 import org.apache.avalon.framework.configuration.Configuration;
-import org.apache.avalon.framework.context.ContextException;
 import org.apache.avalon.framework.logger.AbstractLogEnabled;
 import org.apache.avalon.framework.logger.LogKitLogger;
 import org.apache.avalon.framework.logger.Logger;
@@ -31,6 +30,7 @@ import org.apache.myrmidon.api.TaskContext;
 import org.apache.myrmidon.api.TaskException;
 import org.apache.myrmidon.components.deployer.DefaultDeployer;
 import org.apache.myrmidon.components.executor.DefaultExecutionFrame;
+import org.apache.myrmidon.components.role.DefaultRoleManager;
 import org.apache.myrmidon.framework.Condition;
 import org.apache.myrmidon.interfaces.deployer.Deployer;
 import org.apache.myrmidon.interfaces.deployer.DeploymentException;
@@ -41,6 +41,7 @@ import org.apache.myrmidon.interfaces.model.Target;
 import org.apache.myrmidon.interfaces.model.TypeLib;
 import org.apache.myrmidon.interfaces.type.TypeManager;
 import org.apache.myrmidon.interfaces.workspace.Workspace;
+import org.apache.myrmidon.interfaces.role.RoleManager;
 import org.apache.myrmidon.listeners.ProjectListener;
 
 /**
@@ -141,7 +142,7 @@ public class DefaultWorkspace
     private TaskContext createBaseContext()
         throws TaskException
     {
-        final TaskContext context = new DefaultTaskContext();
+        final TaskContext context = new DefaultTaskContext( m_componentManager );
 
         final String[] names = m_parameters.getNames();
         for( int i = 0; i < names.length; i++ )
@@ -219,9 +220,6 @@ public class DefaultWorkspace
     private ExecutionFrame createExecutionFrame( final Project project )
         throws TaskException
     {
-        final TaskContext context = new DefaultTaskContext( m_baseContext );
-        context.setProperty( TaskContext.BASE_DIRECTORY, project.getBaseDirectory() );
-
         //Create per frame ComponentManager
         final DefaultComponentManager componentManager =
             new DefaultComponentManager( m_componentManager );
@@ -267,6 +265,11 @@ public class DefaultWorkspace
             componentManager.put( Project.ROLE + "/" + name, other );
         }
 
+        // Create and configure the context
+        final DefaultTaskContext context =
+            new DefaultTaskContext( m_baseContext, componentManager );
+        context.setProperty( TaskContext.BASE_DIRECTORY, project.getBaseDirectory() );
+
         final DefaultExecutionFrame frame = new DefaultExecutionFrame();
 
         try
@@ -276,7 +279,6 @@ public class DefaultWorkspace
 
             frame.enableLogging( logger );
             frame.contextualize( context );
-            frame.compose( componentManager );
         }
         catch( final Exception e )
         {
@@ -401,10 +403,10 @@ public class DefaultWorkspace
                     return;
                 }
             }
-            catch( final ContextException ce )
+            catch( final TaskException te )
             {
                 final String message = REZ.getString( "condition-eval.error", name );
-                throw new TaskException( message, ce );
+                throw new TaskException( message, te );
             }
         }
 

proposal/myrmidon/src/java/org/apache/myrmidon/components/workspace/Resources.properties

@@ -15,7 +15,10 @@ no-version.error=No JavaVersion in Context.
 no-name.error=No Name in Context.
 no-dir.error=No Base Directory in Context.
 no-parent.error=Can't set a property with parent scope when context has no parent.
+bad-find-services.error=Unable to find service "{0}".
 bad-scope.error=Unknown property scope! ({0}).
 bad-property.error=Property {0} must have a value of type {1}.
 null-resolved-value.error=Value "{0}" resolved to null.
-bad-resolve.error=Unable to resolve value "{0}".
+bad-resolve.error=Unable to resolve value "{0}".
+bad-find-service.error=Could not find service "{0}".
+bad-service-class.error=Find service "{0}" but it was of type {1} where it was expected to be of type {2}.

proposal/myrmidon/src/java/org/apache/myrmidon/framework/AbstractContainerTask.java

@@ -9,20 +9,21 @@ package org.apache.myrmidon.framework;
 
 import org.apache.avalon.excalibur.i18n.ResourceManager;
 import org.apache.avalon.excalibur.i18n.Resources;
-
-
-import org.apache.avalon.framework.component.ComponentException;
-import org.apache.avalon.framework.component.ComponentManager;
-import org.apache.avalon.framework.component.Composable;
 import org.apache.avalon.framework.configuration.Configuration;
 import org.apache.avalon.framework.configuration.ConfigurationException;
-
+import org.apache.avalon.framework.context.Context;
+import org.apache.avalon.framework.context.ContextException;
 import org.apache.myrmidon.api.AbstractTask;
+import org.apache.myrmidon.api.TaskException;
+import org.apache.myrmidon.api.TaskContext;
 import org.apache.myrmidon.converter.Converter;
 import org.apache.myrmidon.converter.ConverterException;
 import org.apache.myrmidon.interfaces.configurer.Configurer;
 import org.apache.myrmidon.interfaces.converter.MasterConverter;
 import org.apache.myrmidon.interfaces.executor.Executor;
+import org.apache.myrmidon.interfaces.type.TypeFactory;
+import org.apache.myrmidon.interfaces.type.TypeManager;
+import org.apache.myrmidon.interfaces.type.TypeException;
 
 /**
  * This is the class that Task writers should extend to provide custom tasks.
@@ -31,7 +32,6 @@ import org.apache.myrmidon.interfaces.executor.Executor;
  */
 public abstract class AbstractContainerTask
     extends AbstractTask
-    implements Composable
 {
     private final static Resources REZ =
         ResourceManager.getPackageResources( AbstractContainerTask.class );
@@ -45,12 +45,18 @@ public abstract class AbstractContainerTask
     ///For executing sub-elements as tasks
     private Executor m_executor;
 
-    public void compose( final ComponentManager componentManager )
-        throws ComponentException
+    /**
+     * Retrieve context from container.
+     *
+     * @param context the context
+     */
+    public void contextualize( TaskContext context )
+        throws TaskException
     {
-        m_configurer = (Configurer)componentManager.lookup( Configurer.ROLE );
-        m_converter = (MasterConverter)componentManager.lookup( MasterConverter.ROLE );
-        m_executor = (Executor)componentManager.lookup( Executor.ROLE );
+        super.contextualize( context );
+        m_configurer = (Configurer)getService( Configurer.class );
+        m_converter = (MasterConverter)getService( MasterConverter.class );
+        m_executor = (Executor)getService( Executor.class );
     }
 
     /**
@@ -102,6 +108,24 @@ public abstract class AbstractContainerTask
         getConfigurer().configure( object, name, value, getContext() );
     }
 
+    /**
+     * Locates a type factory.
+     */
+    protected final TypeFactory getTypeFactory( final String role )
+        throws TaskException
+    {
+        final TypeManager typeManager = (TypeManager)getService( TypeManager.class );
+        try
+        {
+            return typeManager.getFactory( role );
+        }
+        catch( final TypeException te )
+        {
+            final String message = REZ.getString( "container.no-factory.error", role );
+            throw new TaskException( message, te );
+        }
+    }
+
     /**
      * Convenience method for sub-class to retrieve Configurer.
      *

proposal/myrmidon/src/java/org/apache/myrmidon/framework/AbstractTypeDef.java

@@ -12,9 +12,6 @@ import java.net.URL;
 import java.net.URLClassLoader;
 import org.apache.avalon.excalibur.i18n.ResourceManager;
 import org.apache.avalon.excalibur.i18n.Resources;
-import org.apache.avalon.framework.component.ComponentException;
-import org.apache.avalon.framework.component.ComponentManager;
-import org.apache.avalon.framework.component.Composable;
 import org.apache.myrmidon.api.AbstractTask;
 import org.apache.myrmidon.api.TaskException;
 import org.apache.myrmidon.interfaces.role.RoleManager;
@@ -31,7 +28,6 @@ import org.apache.myrmidon.interfaces.type.TypeManager;
  */
 public abstract class AbstractTypeDef
     extends AbstractTask
-    implements Composable
 {
     private final static Resources REZ =
         ResourceManager.getPackageResources( AbstractTypeDef.class );
@@ -39,15 +35,6 @@ public abstract class AbstractTypeDef
     private File m_lib;
     private String m_name;
     private String m_className;
-    private TypeManager m_typeManager;
-    private RoleManager m_roleManager;
-
-    public void compose( final ComponentManager componentManager )
-        throws ComponentException
-    {
-        m_typeManager = (TypeManager)componentManager.lookup( TypeManager.ROLE );
-        m_roleManager = (RoleManager)componentManager.lookup( RoleManager.ROLE );
-    }
 
     public void setLib( final File lib )
     {
@@ -80,15 +67,17 @@ public abstract class AbstractTypeDef
         }
 
         final String typeName = getTypeName();
-        final String role = m_roleManager.getRoleForName( typeName );
+        final RoleManager roleManager = (RoleManager)getService( RoleManager.class );
+        final String role = roleManager.getRoleForName( typeName );
 
         final ClassLoader classLoader = createClassLoader();
         final DefaultTypeFactory factory = new DefaultTypeFactory( classLoader );
         factory.addNameClassMapping( m_name, m_className );
 
+        final TypeManager typeManager = (TypeManager)getService( TypeManager.class );
         try
         {
-            m_typeManager.registerType( role, m_name, factory );
+            typeManager.registerType( role, m_name, factory );
         }
         catch( final TypeException te )
         {
@@ -116,10 +105,5 @@ public abstract class AbstractTypeDef
         }
     }
 
-    protected final TypeManager getTypeManager()
-    {
-        return m_typeManager;
-    }
-
     protected abstract String getTypeName();
 }

proposal/myrmidon/src/java/org/apache/myrmidon/framework/Resources.properties

@@ -1,6 +1,7 @@
 container.null-value.error=Value ({0}) resolved to null.
 container.bad-resolve.error=Error resolving value ({0}).
 container.bad-config.error=Error converting value.
+container.no-factory.error=Could not locate the type factory for type "{0}".
 
 typedef.no-name.error=Must specify name parameter.
 typedef.no-classname.error=Must specify classname parameter.
@@ -11,7 +12,6 @@ condition.no-resolve.error=Error resolving {0}.
 
 pattern.ifelse-duplicate.error=Can only set one of if/else for pattern data type.
 
-type.no-factory.error=Unable to retrieve DataType factory from TypeManager.
 type.no-create.error=Unable to create datatype.
 type.no-id.error=Id must be specified.
 

proposal/myrmidon/src/java/org/apache/myrmidon/framework/TypeInstanceTask.java

@@ -9,17 +9,13 @@ package org.apache.myrmidon.framework;
 
 import org.apache.avalon.excalibur.i18n.ResourceManager;
 import org.apache.avalon.excalibur.i18n.Resources;
-import org.apache.avalon.framework.component.ComponentException;
-import org.apache.avalon.framework.component.ComponentManager;
 import org.apache.avalon.framework.configuration.Configurable;
 import org.apache.avalon.framework.configuration.Configuration;
 import org.apache.avalon.framework.configuration.ConfigurationException;
 import org.apache.avalon.framework.configuration.DefaultConfiguration;
 import org.apache.myrmidon.api.TaskContext;
 import org.apache.myrmidon.api.TaskException;
-import org.apache.myrmidon.interfaces.type.TypeException;
 import org.apache.myrmidon.interfaces.type.TypeFactory;
-import org.apache.myrmidon.interfaces.type.TypeManager;
 
 /**
  * This is the property "task" to declare a binding of a datatype to a name.
@@ -36,24 +32,6 @@ public class TypeInstanceTask
     private String m_id;
     private Object m_value;
     private boolean m_localScope = true;
-    private TypeFactory m_factory;
-
-    public void compose( final ComponentManager componentManager )
-        throws ComponentException
-    {
-        super.compose( componentManager );
-
-        final TypeManager typeManager = (TypeManager)componentManager.lookup( TypeManager.ROLE );
-        try
-        {
-            m_factory = typeManager.getFactory( DataType.ROLE );
-        }
-        catch( final TypeException te )
-        {
-            final String message = REZ.getString( "type.no-factory.error" );
-            throw new ComponentException( message, te );
-        }
-    }
 
     public void configure( final Configuration configuration )
         throws ConfigurationException
@@ -85,7 +63,8 @@ public class TypeInstanceTask
 
         try
         {
-            m_value = m_factory.create( configuration.getName() );
+            final TypeFactory typeFactory = getTypeFactory( DataType.ROLE );
+            m_value = typeFactory.create( configuration.getName() );
         }
         catch( final Exception e )
         {

proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/executor/ExecutionFrame.java

@@ -24,6 +24,4 @@ public interface ExecutionFrame
     Logger getLogger();
 
     TaskContext getContext();
-
-    ComponentManager getComponentManager();
 }