mcconnell 2002/12/27 08:38:54
Modified: merlin/src/java/org/apache/avalon/merlin/block Block.java
DefaultBlock.java
Log:
Refactored implementation to extend from Appliance. Implementation now
parrallels Appliance in that is managing the establishment of a compoennt - but
in the Block case, the component is a containement heirachy.
Revision Changes Path
1.5 +7 -12
avalon-sandbox/merlin/src/java/org/apache/avalon/merlin/block/Block.java
Index: Block.java
===================================================================
RCS file:
/home/cvs/avalon-sandbox/merlin/src/java/org/apache/avalon/merlin/block/Block.java,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- Block.java 17 Dec 2002 04:45:21 -0000 1.4
+++ Block.java 27 Dec 2002 16:38:54 -0000 1.5
@@ -51,23 +51,18 @@
package org.apache.avalon.merlin.block;
import org.apache.avalon.assembly.appliance.Appliance;
+import org.apache.avalon.merlin.container.Container;
/**
- * A block is a deployment model supporting composite components.
+ * A block is a deployment model supporting composite components. A block is
+ * both an appliance and a proxy to a container. As an appliance it manages
+ * the deployment of a root container. As a container it handles delatation
+ * of containment lifecycle operations to the managed container instance.
*
* @author <a href="mailto:avalon-dev@jakarta.apache.org";>Avalon Development
Team</a>
* @version $Revision$ $Date$
*/
-public interface Block
+public interface Block extends Appliance, Container
{
static final String AVALON_BLOCK_KEY = "Avalon-Block";
-
-
- /**
- * Get appliance managing the root container.
- * @return the root container appliance
- */
- Appliance getAppliance();
-
}
-
1.9 +105 -42
avalon-sandbox/merlin/src/java/org/apache/avalon/merlin/block/DefaultBlock.java
Index: DefaultBlock.java
===================================================================
RCS file:
/home/cvs/avalon-sandbox/merlin/src/java/org/apache/avalon/merlin/block/DefaultBlock.java,v
retrieving revision 1.8
retrieving revision 1.9
diff -u -r1.8 -r1.9
--- DefaultBlock.java 17 Dec 2002 04:45:21 -0000 1.8
+++ DefaultBlock.java 27 Dec 2002 16:38:54 -0000 1.9
@@ -12,10 +12,17 @@
import java.util.Map;
import java.util.Hashtable;
-import org.apache.avalon.framework.logger.Logger;
-import org.apache.avalon.framework.logger.AbstractLogEnabled;
+import org.apache.avalon.assembly.appliance.Appliance;
import org.apache.avalon.assembly.appliance.DefaultAppliance;
+import org.apache.avalon.assembly.appliance.ApplianceContext;
+import org.apache.avalon.assembly.appliance.ApplianceException;
import org.apache.avalon.assembly.engine.EngineClassLoader;
+import org.apache.avalon.assembly.lifestyle.LifestyleException;
+import org.apache.avalon.assembly.lifestyle.LifestyleService;
+import org.apache.avalon.assembly.lifecycle.AssemblyService;
+import org.apache.avalon.assembly.lifecycle.AssemblyException;
+import org.apache.avalon.framework.logger.Logger;
+import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.avalon.framework.activity.Initializable;
import org.apache.avalon.framework.context.Context;
import org.apache.avalon.framework.context.Contextualizable;
@@ -23,101 +30,157 @@
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.ConfigurationException;
-import org.apache.avalon.assembly.engine.model.ClasspathDescriptor;
-import org.apache.avalon.assembly.appliance.Appliance;
-import org.apache.avalon.assembly.lifestyle.LifestyleException;
import org.apache.avalon.merlin.container.DefaultContainer;
import org.apache.avalon.merlin.container.ContainerDescriptor;
+import org.apache.avalon.merlin.container.Container;
import org.apache.avalon.meta.info.Type;
+import org.apache.avalon.meta.info.builder.XMLTypeCreator;
import org.apache.avalon.meta.info.StageDescriptor;
import org.apache.avalon.meta.info.DependencyDescriptor;
+import org.apache.avalon.meta.model.builder.XMLProfileCreator;
import org.apache.avalon.meta.model.Profile;
-public class DefaultBlock extends AbstractLogEnabled implements Block
+/**
+ * The default implementation of a Block. The implementation provides
+ * support for convinence operations related to its role as a container
+ * by delegating to the container it is managing. As an appliance it is
+ * responsible for the establishment of a containment heirachy that
+ * represents the implemetation model for the block.
+ */
+public class DefaultBlock extends DefaultAppliance implements Block
{
//==============================================================
// static
//==============================================================
- public static final Attributes.Name BLOCK_NAME = new Attributes.Name(
"Block-Name" );
+ public static final Attributes.Name BLOCK_PACKAGE = new Attributes.Name(
"Block-Package" );
- public static String getName( Manifest manifest )
+ public static String getPackageName( Manifest manifest )
{
Attributes attributes = manifest.getAttributes(
Block.AVALON_BLOCK_KEY );
if( attributes == null )
{
return null;
}
- if( attributes.containsKey( BLOCK_NAME ) )
+ if( attributes.containsKey( BLOCK_PACKAGE ) )
{
- return (String) attributes.get( BLOCK_NAME );
+ return (String) attributes.get( BLOCK_PACKAGE );
}
return null;
}
+ public static boolean isBlock( Manifest manifest )
+ {
+ if( manifest == null )
+ {
+ return false;
+ }
+ return ( manifest.getAttributes( Block.AVALON_BLOCK_KEY ) != null );
+ }
+
+
//==============================================================
// state
//==============================================================
- private String m_name;
+ private Container m_container;
- private Manifest m_manifest;
+ private boolean m_assembled = false;
- private URL m_url;
+ //==============================================================
+ // constructor
+ //==============================================================
- /**
- * The applaince holding the root container.
- */
- private Appliance m_appliance;
+ public DefaultBlock(
+ EngineClassLoader engine, LifestyleService lifestyle, AssemblyService
assembly,
+ ApplianceContext context, Context system, Logger logger )
+ throws ApplianceException
+ {
+ super( engine, lifestyle, assembly, context, system, logger );
+ }
//==============================================================
- // constructor
+ // Block
//==============================================================
- public DefaultBlock( Appliance appliance, URL url, Manifest manifest )
- throws BlockException
+ /**
+ * Assemble the appliance. The implementation extends the default
+ * appliance behavior by instantiating the container it is managing,
+ * and applying assembly to the container instance. This results in
+ * container creating appliance instances for the component is is
+ * managing together with assembly of its sub-containers.
+ *
+ * @exception AssemblyException if an error occurs during appliance
assembly
+ */
+ public void assemble() throws AssemblyException
{
- if( appliance == null )
+ if( m_assembled )
{
- throw new NullPointerException( "appliance" );
+ return;
}
- if( url == null )
+
+ if( getLogger().isDebugEnabled() )
{
- throw new NullPointerException( "url" );
+ getLogger().debug("block assembly" );
}
- if( manifest == null )
+
+ super.assemble();
+
+ try
{
- throw new NullPointerException( "manifest" );
+ m_assembled = true;
+ m_container = (Container) super.access();
+ m_container.assemble();
}
+ catch( Throwable e )
+ {
+ m_assembled = false;
+ final String error = "Unable to establish containment
implemetation.";
+ throw new AssemblyException( error, e );
+ }
+ }
- m_url = url;
- m_manifest = manifest;
- m_appliance = appliance;
+ /**
+ * Terminate the block. If a container has been established, the
implemetation
+ * will relase the container and continue with appliance termination.
+ */
+ public void terminate()
+ {
+ if( m_container != null )
+ {
+ release( m_container );
+ m_container = null;
+ }
+ super.terminate();
}
- //==============================================================
- // Block
- //==============================================================
+
//-------------------------------------------------------------------------------
+ // Container
+
//-------------------------------------------------------------------------------
/**
- * Return the name of the block.
- * @return the name
+ * Convinience operation to startup the components in the container.
+ * @exception Exception if a container startup error occurs
*/
- public String getName()
+ public void startup() throws Exception
{
- if( m_name == null )
+ if( !m_assembled )
{
- m_name = getName( m_manifest );
+ throw new IllegalStateException( "assembly" );
}
- return m_name;
+ m_container.startup();
}
/**
- * Get appliance managing the root container.
- * @return the root container appliance
+ * Convinience operation to shutdown the components in the container.
+ * @exception Exception if a container shutdown error occurs
*/
- public Appliance getAppliance()
+ public void shutdown() throws Exception
{
- return m_appliance;
+ if( !m_assembled )
+ {
+ throw new IllegalStateException( "assembly" );
+ }
+ m_container.shutdown();
}
}
--
To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]>
For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
