org.eclipse.jetty.server.handler.AbstractHandlerContainer Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2013 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 org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.HandlerContainer;
import org.eclipse.jetty.util.LazyList;
import org.eclipse.jetty.util.TypeUtil;
/* ------------------------------------------------------------ */
/** Abstract Handler Container.
* This is the base class for handlers that may contain other handlers.
*
*/
public abstract class AbstractHandlerContainer extends AbstractHandler implements HandlerContainer
{
/* ------------------------------------------------------------ */
public AbstractHandlerContainer()
{
}
/* ------------------------------------------------------------ */
public Handler[] getChildHandlers()
{
Object list = expandChildren(null,null);
return (Handler[])LazyList.toArray(list, Handler.class);
}
/* ------------------------------------------------------------ */
public Handler[] getChildHandlersByClass(Class byclass)
{
Object list = expandChildren(null,byclass);
return (Handler[])LazyList.toArray(list, byclass);
}
/* ------------------------------------------------------------ */
public T getChildHandlerByClass(Class byclass)
{
// TODO this can be more efficient?
Object list = expandChildren(null,byclass);
if (list==null)
return null;
return (T)LazyList.get(list, 0);
}
/* ------------------------------------------------------------ */
protected Object expandChildren(Object list, Class byClass)
{
return list;
}
/* ------------------------------------------------------------ */
protected Object expandHandler(Handler handler, Object list, Class byClass)
{
if (handler==null)
return list;
if (byClass==null || byClass.isAssignableFrom(handler.getClass()))
list=LazyList.add(list, handler);
if (handler instanceof AbstractHandlerContainer)
list=((AbstractHandlerContainer)handler).expandChildren(list, byClass);
else if (handler instanceof HandlerContainer)
{
HandlerContainer container = (HandlerContainer)handler;
Handler[] handlers=byClass==null?container.getChildHandlers():container.getChildHandlersByClass(byClass);
list=LazyList.addArray(list, handlers);
}
return list;
}
/* ------------------------------------------------------------ */
public static T findContainerOf(HandlerContainer root,Classtype, Handler handler)
{
if (root==null || handler==null)
return null;
Handler[] branches=root.getChildHandlersByClass(type);
if (branches!=null)
{
for (Handler h:branches)
{
T container = (T)h;
Handler[] candidates = container.getChildHandlersByClass(handler.getClass());
if (candidates!=null)
{
for (Handler c:candidates)
if (c==handler)
return container;
}
}
}
return null;
}
/* ------------------------------------------------------------ */
public void dump(Appendable out,String indent) throws IOException
{
dumpThis(out);
dump(out,indent,getBeans(),TypeUtil.asList(getHandlers()));
}
}