--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/eclipse/jetty/server/handler/HandlerWrapper.java	Wed Sep 07 21:15:48 2016 -0600
@@ -0,0 +1,182 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2014 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();
+    }
+
+}