/*
* $Header: /home/cvs/jakarta-struts/src/share/org/apache/struts/tiles/xmlDefinition/FactorySet.java,v 1.1 2002/06/25 03:15:43 craigmcc Exp $
* $Revision: 1.1 $
* $Date: 2002/06/25 03:15:43 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999-2002 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 acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Struts", 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 names without prior written
* permission of the Apache Group.
*
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.struts.tiles.xmlDefinition;
import org.apache.struts.tiles.ComponentDefinitionsFactory;
import org.apache.struts.tiles.ComponentDefinition;
import org.apache.struts.tiles.NoSuchDefinitionException;
import org.apache.struts.tiles.DefinitionsFactoryException;
import org.apache.struts.tiles.FactoryNotFoundException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletContext;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;
/**
* Component Definitions factory.
* This factory contains several factories identified by a key. The
* getDefinition() method first look for the factory key, retrieve or create this
* factory and then call getDefinition() on the found factory.
*/
public abstract class FactorySet implements ComponentDefinitionsFactory
{
/** Loaded factories */
protected Map factories=null;
/**
* Extract key that will be used to get the sub factory.
* @param name Name of requested definition
* @param request Current servlet request.
* @param servletContext Current servlet context
*/
abstract protected Object getDefinitionsFactoryKey(String name, ServletRequest request, ServletContext servletContext);
/**
* Get default factory.
* @return Default factory
*/
abstract protected DefinitionsFactory getDefaultFactory();
/**
* Get a factory by its key.
* If key is null, return defaultFactory.
* Search in loaded factory. If not found, call create factory, and store return value in
* loaded factories.
* @param key Key of requested definition
* @param request Current servlet request.
* @param servletContext Current servlet context
* @throws DefinitionsFactoryException If an error occur while creating factory.
*/
protected DefinitionsFactory getFactory(Object key, ServletRequest request, ServletContext servletContext)
throws DefinitionsFactoryException
{
if(key == null )
return getDefaultFactory();
Object factory = factories.get( key );
if( factory == null )
{
// synchronize creation to avoid double creation by separate threads.
// Also, check if factory hasn't been created while waiting for synchronized
// section.
synchronized(factories)
{
factory = factories.get( key );
if( factory == null )
{
factory = createFactory( key, request, servletContext);
factories.put( key, factory );
} // end if
} // end synchronized
} // end if
return (DefinitionsFactory)factory;
}
/**
* Get a definition by its name.
* @throws DefinitionsFactoryException An error occur while getting
* definition.
* @param name Name of requested definition
* @param request Current servlet request.
* @param servletContext Current servlet context
* @throws NoSuchDefinitionException No definition found for specified name
* @throws DefinitionsFactoryException General exception
*/
public ComponentDefinition getDefinition(String name, ServletRequest request, ServletContext servletContext)
throws NoSuchDefinitionException, DefinitionsFactoryException
{
if( factories == null )
throw new FactoryNotFoundException( "No definitions factory defined" );
Object key = getDefinitionsFactoryKey( name, request, servletContext);
DefinitionsFactory factory = getFactory( key, request, servletContext);
return factory.getDefinition( name, request, servletContext );
}
/**
* Create a factory for specified key.
* This method is called by getFactory() when the requested factory doesn't already exist.
* Must return a factory, even a default one.
* Real implementation need to provide this method.
* @param key Key of requested definition
* @param request Current servlet request.
* @param servletContext Current servlet context
* @throws DefinitionsFactoryException If an error occur while creating factory.
*/
abstract protected DefinitionsFactory createFactory(Object key, ServletRequest request, ServletContext servletContext)
throws DefinitionsFactoryException;
/**
* Init factory set.
* @param servletContext Current servlet context
* @param properties properties used to initialized factory set;
*/
abstract public void initFactory(ServletContext servletContext, Map properties)
throws DefinitionsFactoryException;
/**
*
*/
public FactorySet()
{
factories = new HashMap();
}
/**
*
*/
public String toString()
{
Iterator i = factories.values().iterator();
StringBuffer buff = new StringBuffer( "all FactorySet's factory : \n" );
while( i.hasNext() )
{
buff.append( i.next().toString() ).append("\n");
}
return buff.toString();
}
}