// ========================================================================
// Copyright (c) 2004-2009 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
package org.eclipse.jetty.server.handler;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.util.component.LifeCycle;
/* ------------------------------------------------------------ */
/** A <code>HandlerWrapper</code> acts as a {@link Handler} but delegates the {@link Handler#handle handle} method and
* {@link LifeCycle life cycle} events to a delegate. This is primarily used to implement the <i>Decorator</i> pattern.
*
*/
public class HandlerWrapper extends AbstractHandlerContainer
{
protected Handler _handler;
/* ------------------------------------------------------------ */
/**
*
*/
public HandlerWrapper()
{
}
/* ------------------------------------------------------------ */
/**
* @return Returns the handlers.
*/
public Handler getHandler()
{
return _handler;
}
/* ------------------------------------------------------------ */
/**
* @return Returns the handlers.
*/
public Handler[] getHandlers()
{
if (_handler==null)
return new Handler[0];
return new Handler[] {_handler};
}
/* ------------------------------------------------------------ */
/**
* @param handler Set the {@link Handler} which should be wrapped.
*/
public void setHandler(Handler handler)
{
if (isStarted())
throw new IllegalStateException(STARTED);
Handler old_handler = _handler;
_handler = handler;
if (handler!=null)
handler.setServer(getServer());
if (getServer()!=null)
getServer().getContainer().update(this, old_handler, handler, "handler");
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.thread.AbstractLifeCycle#doStart()
*/
@Override
protected void doStart() throws Exception
{
if (_handler!=null)
_handler.start();
super.doStart();
}
/* ------------------------------------------------------------ */
/*
* @see org.eclipse.thread.AbstractLifeCycle#doStop()
*/
@Override
protected void doStop() throws Exception
{
if (_handler!=null)
_handler.stop();
super.doStop();
}
/* ------------------------------------------------------------ */
public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
{
if (_handler!=null && isStarted())
{
_handler.handle(target,baseRequest, request, response);
}
}
/* ------------------------------------------------------------ */
@Override
public void setServer(Server server)
{
Server old_server=getServer();
if (server==old_server)
return;
if (isStarted())
throw new IllegalStateException(STARTED);
super.setServer(server);
Handler h=getHandler();
if (h!=null)
h.setServer(server);
if (server!=null && server!=old_server)
server.getContainer().update(this, null,_handler, "handler");
}
/* ------------------------------------------------------------ */
@Override
protected Object expandChildren(Object list, Class byClass)
{
return expandHandler(_handler,list,byClass);
}
/* ------------------------------------------------------------ */
public <H extends Handler> H getNestedHandlerByClass(Class<H> byclass)
{
HandlerWrapper h=this;
while (h!=null)
{
if (byclass.isInstance(h))
return (H)h;
Handler w = h.getHandler();
if (w instanceof HandlerWrapper)
h=(HandlerWrapper)w;
else break;
}
return null;
}
/* ------------------------------------------------------------ */
@Override
public void destroy()
{
if (!isStopped())
throw new IllegalStateException("!STOPPED");
Handler child=getHandler();
if (child!=null)
{
setHandler(null);
child.destroy();
}
super.destroy();
}
}