* Moved package org.apache.myrmidon.services to org.apache.myrmidon.interfaces.service.

* Added ServiceManager interface, and several implementations.


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271311 13f79535-47bb-0310-9956-ffa450edef68

proposal/myrmidon/src/java/org/apache/myrmidon/components/service/DefaultServiceManager.java

@@ -0,0 +1,144 @@
+/*
+ * 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.myrmidon.components.service;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import org.apache.avalon.excalibur.i18n.ResourceManager;
+import org.apache.avalon.excalibur.i18n.Resources;
+import org.apache.avalon.framework.activity.Disposable;
+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.interfaces.service.ServiceException;
+import org.apache.myrmidon.interfaces.service.ServiceFactory;
+import org.apache.myrmidon.interfaces.service.ServiceManager;
+import org.apache.myrmidon.interfaces.type.TypeException;
+import org.apache.myrmidon.interfaces.type.TypeFactory;
+import org.apache.myrmidon.interfaces.type.TypeManager;
+
+/**
+ * A service manager implementation.  This implementation takes care of
+ * creating service instances, using a {@link ServiceFactory}, and running the
+ * service instances through the service lifecycle.  Service creation happens
+ * on demand.
+ *
+ * <p>This implementation uses a TypeManager to locate the service factories.
+ *
+ * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
+ * @version $Revision$ $Date$
+ */
+public class DefaultServiceManager
+    implements ServiceManager, Composable, Disposable
+{
+    private final static Resources REZ
+        = ResourceManager.getPackageResources( DefaultServiceManager.class );
+
+    /** Map from service class -> service object. */
+    private Map m_services = new HashMap();
+
+    private TypeFactory m_typeFactory;
+
+    /**
+     * Locate the components used by this service manager.
+     */
+    public void compose( final ComponentManager componentManager ) throws ComponentException
+    {
+        final TypeManager typeManager = (TypeManager)componentManager.lookup( TypeManager.ROLE );
+        try
+        {
+            m_typeFactory = typeManager.getFactory( ServiceFactory.class );
+        }
+        catch( final TypeException e )
+        {
+            throw new ComponentException( e.getMessage(), e );
+        }
+    }
+
+    /**
+     * Disposes this service manager, and all services created by it.
+     */
+    public void dispose()
+    {
+        // Dispose the services
+        for( Iterator iterator = m_services.values().iterator(); iterator.hasNext(); )
+        {
+            final Object object = iterator.next();
+            if( object instanceof Disposable )
+            {
+                ( (Disposable)object ).dispose();
+            }
+        }
+
+        // Ditch state
+        m_services = null;
+        m_typeFactory = null;
+    }
+
+    /**
+     * Determines if this service manager contains a particular service.
+     */
+    public boolean hasService( Class serviceType )
+    {
+        // If we have already instantiated the service, or if we know how
+        // to instantiate it, then return true
+        if( m_services.containsKey( serviceType ) )
+        {
+            return true;
+        }
+        if( m_typeFactory.canCreate( serviceType.getName() ) )
+        {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Locates a service instance.
+     */
+    public Object getService( Class serviceType )
+        throws ServiceException
+    {
+        Object service = m_services.get( serviceType );
+        if( service == null )
+        {
+            // Create the service
+            service = createService( serviceType );
+            m_services.put( serviceType, service );
+        }
+
+        return service;
+    }
+
+    /**
+     * Creates the service object for a service class.
+     */
+    private Object createService( Class serviceType ) throws ServiceException
+    {
+        try
+        {
+            final ServiceFactory factory = (ServiceFactory)m_typeFactory.create( serviceType.getName() );
+
+            // Create the service
+            final Object service = factory.createService();
+            if( ! serviceType.isInstance( service ) )
+            {
+                final String message = REZ.getString( "mismatched-service-type.error", serviceType.getName(), service.getClass().getName() );
+                throw new ServiceException( message );
+            }
+            return service;
+        }
+        catch( Exception e )
+        {
+            final String message = REZ.getString( "create-service.error", serviceType.getName() );
+            throw new ServiceException( message, e );
+        }
+    }
+}

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

@@ -0,0 +1,3 @@
+unknown-service-type.error=Unknown service type {0}.
+mismatched-service-type.error=Service factory for type {0} produced an object of unexpected type {1}.
+create-service.error=Could not create service {0}.

proposal/myrmidon/src/java/org/apache/myrmidon/framework/factorys/ExecManagerFactory.java

@@ -12,8 +12,8 @@ import org.apache.aut.nativelib.ExecException;
 import org.apache.aut.nativelib.impl.DefaultExecManager;
 import org.apache.avalon.excalibur.i18n.ResourceManager;
 import org.apache.avalon.excalibur.i18n.Resources;
-import org.apache.myrmidon.services.ServiceException;
-import org.apache.myrmidon.services.ServiceFactory;
+import org.apache.myrmidon.interfaces.service.ServiceException;
+import org.apache.myrmidon.interfaces.service.ServiceFactory;
 
 /**
  * A Factory responsible for creating the ExecManager service.

proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/ComponentManagerAdaptor.java

@@ -0,0 +1,52 @@
+/*
+ * 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.myrmidon.interfaces.service;
+
+import org.apache.avalon.framework.component.ComponentException;
+import org.apache.avalon.framework.component.ComponentManager;
+
+/**
+ * An adaptor from {@link ComponentManager} to {@link ServiceManager}.
+ *
+ * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
+ * @version $Revision$ $Date$
+ */
+public class ComponentManagerAdaptor
+    implements ServiceManager
+{
+    private final ComponentManager m_componentManager;
+
+    public ComponentManagerAdaptor( final ComponentManager componentManager )
+    {
+        m_componentManager = componentManager;
+    }
+
+    /**
+     * Determines if this service manager contains a particular service.
+     */
+    public boolean hasService( Class serviceType )
+    {
+        return m_componentManager.hasComponent( serviceType.getName() );
+    }
+
+    /**
+     * Locates a service instance.
+     */
+    public Object getService( Class serviceType )
+        throws ServiceException
+    {
+        try
+        {
+            return m_componentManager.lookup( serviceType.getName() );
+        }
+        catch( ComponentException e )
+        {
+            throw new ServiceException( e.getMessage(), e );
+        }
+    }
+}

proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/MultiSourceServiceManager.java

@@ -0,0 +1,79 @@
+/*
+ * 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.myrmidon.interfaces.service;
+
+import java.util.ArrayList;
+import org.apache.avalon.excalibur.i18n.ResourceManager;
+import org.apache.avalon.excalibur.i18n.Resources;
+
+/**
+ * A service manager that aggregates services from several
+ * {@link ServiceManager} objects.
+ *
+ * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
+ * @version $Revision$ $Date$
+ */
+public class MultiSourceServiceManager
+    implements ServiceManager
+{
+    private final static Resources REZ
+        = ResourceManager.getPackageResources( MultiSourceServiceManager.class );
+
+    /** The source service managers, in order. */
+    private final ArrayList m_sources = new ArrayList();
+
+    /**
+     * Adds a service manager to the end of the source list.
+     */
+    public void add( final ServiceManager mgr )
+    {
+        m_sources.add( mgr );
+    }
+
+    /**
+     * Determines if this service manager contains a particular service.
+     *
+     * @param serviceType The service interface.
+     */
+    public boolean hasService( Class serviceType )
+    {
+        for( int i = 0; i < m_sources.size(); i++ )
+        {
+            final ServiceManager serviceManager = (ServiceManager)m_sources.get( i );
+            if( serviceManager.hasService( serviceType ) )
+            {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Locates a service instance.
+     *
+     * @param serviceType The service interface.
+     * @return The service instance.  The returned object is guaranteed to
+     *         implement the service interface.
+     * @throws ServiceException If the service does not exist.
+     */
+    public Object getService( Class serviceType )
+        throws ServiceException
+    {
+        for( int i = 0; i < m_sources.size(); i++ )
+        {
+            final ServiceManager serviceManager = (ServiceManager)m_sources.get( i );
+            if( serviceManager.hasService( serviceType ) )
+            {
+                return serviceManager.getService( serviceType );
+            }
+        }
+
+        final String message = REZ.getString( "unknown-service.error", serviceType.getName() );
+        throw new ServiceException( message );
+    }
+}

proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/Resources.properties

@@ -0,0 +1 @@
+unknown-service.error=Unknown service {0}.

proposal/myrmidon/src/java/org/apache/myrmidon/services/ServiceException.java → proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/ServiceException.java

@@ -5,7 +5,7 @@
  * version 1.1, a copy of which has been included with this distribution in
  * the LICENSE.txt file.
  */
-package org.apache.myrmidon.services;
+package org.apache.myrmidon.interfaces.service;
 
 import org.apache.avalon.framework.CascadingException;
 

proposal/myrmidon/src/java/org/apache/myrmidon/services/ServiceFactory.java → proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/ServiceFactory.java

@@ -5,7 +5,7 @@
  * version 1.1, a copy of which has been included  with this distribution in
  * the LICENSE.txt file.
  */
-package org.apache.myrmidon.services;
+package org.apache.myrmidon.interfaces.service;
 
 /**
  * A ServiceFactory is used to create a service for use in the
@@ -17,6 +17,8 @@ package org.apache.myrmidon.services;
  */
 public interface ServiceFactory
 {
+    String ROLE = ServiceFactory.class.getName();
+
     /**
      * Create a service that coresponds to this factory.
      * This method is usually called after the factory has been

proposal/myrmidon/src/java/org/apache/myrmidon/interfaces/service/ServiceManager.java

@@ -0,0 +1,40 @@
+/*
+ * 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.myrmidon.interfaces.service;
+
+import org.apache.avalon.framework.component.Component;
+
+/**
+ * Manages a set of services.
+ *
+ * @author <a href="mailto:adammurdoch@apache.org">Adam Murdoch</a>
+ * @version $Revision$ $Date$
+ */
+public interface ServiceManager
+    extends Component
+{
+    String ROLE = ServiceManager.class.getName();
+
+    /**
+     * Determines if this service manager contains a particular service.
+     *
+     * @param serviceType The service interface.
+     */
+    boolean hasService( Class serviceType );
+
+    /**
+     * Locates a service instance.
+     *
+     * @param serviceType The service interface.
+     * @return The service instance.  The returned object is guaranteed to
+     *         implement the service interface.
+     * @throws ServiceException If the service does not exist.
+     */
+    Object getService( Class serviceType )
+        throws ServiceException;
+}

proposal/myrmidon/src/main/org/apache/tools/ant/taskdefs/exec/Execute.java

@@ -17,7 +17,7 @@ import org.apache.aut.nativelib.ExecMetaData;
 import org.apache.avalon.excalibur.io.IOUtil;
 import org.apache.myrmidon.api.TaskException;
 import org.apache.myrmidon.framework.factorys.ExecManagerFactory;
-import org.apache.myrmidon.services.ServiceException;
+import org.apache.myrmidon.interfaces.service.ServiceException;
 
 /**
  * Runs an external program.

proposal/myrmidon/src/todo/org/apache/tools/ant/taskdefs/exec/Execute.java

@@ -17,7 +17,7 @@ import org.apache.aut.nativelib.ExecMetaData;
 import org.apache.avalon.excalibur.io.IOUtil;
 import org.apache.myrmidon.api.TaskException;
 import org.apache.myrmidon.framework.factorys.ExecManagerFactory;
-import org.apache.myrmidon.services.ServiceException;
+import org.apache.myrmidon.interfaces.service.ServiceException;
 
 /**
  * Runs an external program.