| // |
| // ======================================================================== |
| // Copyright (c) 1995-2016 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 java.util.Arrays; |
| import java.util.List; |
| |
| import javax.servlet.ServletException; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpServletResponse; |
| |
| import org.eclipse.jetty.http.HttpStatus; |
| import org.eclipse.jetty.server.Handler; |
| import org.eclipse.jetty.server.HandlerContainer; |
| import org.eclipse.jetty.server.Request; |
| import org.eclipse.jetty.server.Server; |
| import org.eclipse.jetty.util.annotation.ManagedAttribute; |
| import org.eclipse.jetty.util.annotation.ManagedObject; |
| 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. |
| * |
| */ |
| @ManagedObject("Handler wrapping another Handler") |
| public class HandlerWrapper extends AbstractHandlerContainer |
| { |
| protected Handler _handler; |
| |
| /* ------------------------------------------------------------ */ |
| /** |
| * |
| */ |
| public HandlerWrapper() |
| { |
| } |
| |
| /* ------------------------------------------------------------ */ |
| /** |
| * @return Returns the handlers. |
| */ |
| @ManagedAttribute(value="Wrapped Handler", readonly=true) |
| public Handler getHandler() |
| { |
| return _handler; |
| } |
| |
| /* ------------------------------------------------------------ */ |
| /** |
| * @return Returns the handlers. |
| */ |
| @Override |
| 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); |
| |
| // check for loops |
| if (handler==this || (handler instanceof HandlerContainer && |
| Arrays.asList(((HandlerContainer)handler).getChildHandlers()).contains(this))) |
| throw new IllegalStateException("setHandler loop"); |
| |
| if (handler!=null) |
| handler.setServer(getServer()); |
| |
| Handler old=_handler; |
| _handler=handler; |
| updateBean(old,_handler,true); |
| } |
| |
| /* ------------------------------------------------------------ */ |
| /** |
| * Replace the current handler with another HandlerWrapper |
| * linked to the current handler. |
| * <p> |
| * This is equivalent to: |
| * <pre> |
| * wrapper.setHandler(getHandler()); |
| * setHandler(wrapper); |
| * </pre> |
| * @param wrapper the wrapper to insert |
| */ |
| public void insertHandler(HandlerWrapper wrapper) |
| { |
| if (wrapper==null) |
| throw new IllegalArgumentException(); |
| |
| HandlerWrapper tail = wrapper; |
| while(tail.getHandler() instanceof HandlerWrapper) |
| tail=(HandlerWrapper)tail.getHandler(); |
| if (tail.getHandler()!=null) |
| throw new IllegalArgumentException("bad tail of inserted wrapper chain"); |
| |
| Handler next=getHandler(); |
| setHandler(wrapper); |
| tail.setHandler(next); |
| } |
| |
| /* ------------------------------------------------------------ */ |
| @Override |
| public void handle(String target, Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException |
| { |
| Handler handler=_handler; |
| if (handler!=null) |
| handler.handle(target,baseRequest, request, response); |
| } |
| |
| /* ------------------------------------------------------------ */ |
| @Override |
| protected void expandChildren(List<Handler> list, Class<?> byClass) |
| { |
| expandHandler(_handler,list,byClass); |
| } |
| |
| /* ------------------------------------------------------------ */ |
| @Override |
| public void destroy() |
| { |
| if (!isStopped()) |
| throw new IllegalStateException("!STOPPED"); |
| Handler child=getHandler(); |
| if (child!=null) |
| { |
| setHandler(null); |
| child.destroy(); |
| } |
| super.destroy(); |
| } |
| |
| } |