/* ====================================================================
* Loom Software License, version 1.1
*
* Copyright (c) 2003, Loom Group. 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. Neither the name of the Loom Group nor the name "Loom" nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS 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
* COPYRIGHT OWNER OR 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.
*
* ====================================================================
*
* Loom includes code from the Apache Software Foundation
*
* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 1997-2003 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 acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software
* itself, if and wherever such third-party acknowledgments
* normally appear.
*
* 4. The names "Jakarta", "Avalon", 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 name, without prior written
* permission of the Apache Software Foundation.
*
* 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.
*/
package org.codehaus.loom.components.manager;
import java.util.HashMap;
import java.util.Map;
import org.codehaus.dna.AbstractLogEnabled;
import org.codehaus.dna.Active;
import org.codehaus.loom.interfaces.LoomException;
import org.codehaus.loom.interfaces.SystemManager;
/**
* This is abstract implementation of SystemManager.
*
* @author Peter Donald
*/
public abstract class AbstractSystemManager
extends AbstractLogEnabled
implements SystemManager, Active
{
private final Map m_entries = new HashMap();
private SubContext m_subContext;
public void initialize()
throws Exception
{
m_subContext = new SubContext( this, null, null );
}
public void dispose()
{
m_subContext = null;
}
/**
* @see SystemManager#register(String, Object)
*/
public synchronized void register( final String name,
final Object object )
throws LoomException, IllegalArgumentException
{
checkRegister( name, object );
final Object exportedObject = export( name, object );
m_entries.put( name, exportedObject );
}
/**
* @see SystemManager#unregister(String)
*/
public synchronized void unregister( final String name )
throws LoomException
{
final Object entry = m_entries.remove( name );
if( null == entry )
{
return;
}
unexport( name, entry );
}
/**
* Returns the subcontext of the specified name. If it does not exist it is
* created.
*
* @return the subcontext with the specified name
* @throws LoomException if context cannot be created or retrieved
*/
public SystemManager getSubContext( final String parent,
final String type )
throws LoomException
{
return m_subContext.getSubContext( parent, type );
}
/**
* Export the object to the particular management medium using the supplied
* object and interfaces. This needs to be implemented by subclasses.
*
* @param name the name of object
* @param object the object
* @return the exported object
* @throws LoomException if an error occurs
*/
protected abstract Object export( String name, Object object )
throws LoomException;
/**
* Stop the exported object from being managed.
*
* @param name the name of object
* @param exportedObject the object return by export
* @throws LoomException if an error occurs
*/
protected abstract void unexport( String name, Object exportedObject )
throws LoomException;
/**
* Helper method to help check before an objects registration. Verifies name
* and object are not null and verifies no entry exists using name.
*
* @param name the name of object
* @param object the object to be registered
* @throws LoomException if name already exists
* @throws IllegalArgumentException if name or object is null
*/
private void checkRegister( final String name, final Object object )
throws LoomException, IllegalArgumentException
{
if( null == object )
{
throw new NullPointerException( "object" );
}
if( null == name )
{
throw new NullPointerException( "name" );
}
if( null != m_entries.get( name ) )
{
final String message = name +
" already registered in SystemManager";
throw new LoomException( message );
}
}
}