Jetty example source code file (ContextHandlerCollection.java)

This example Jetty source code file (ContextHandlerCollection.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Jetty tags/keywords

class, contexthandler, contexthandler, exception, handler, handler, http, illegalargumentexception, io, ioexception, map, map, object, pathmap, pathmap, request, response, servlet, string, util

The Jetty ContextHandlerCollection.java source code

//========================================================================
//Copyright 2006 Mort Bay Consulting Pty. Ltd.
//------------------------------------------------------------------------
//Licensed under the Apache License, Version 2.0 (the "License");
//you may not use this file except in compliance with the License.
//You may obtain a copy of the License at 
//http://www.apache.org/licenses/LICENSE-2.0
//Unless required by applicable law or agreed to in writing, software
//distributed under the License is distributed on an "AS IS" BASIS,
//WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//See the License for the specific language governing permissions and
//limitations under the License.
//========================================================================

package org.mortbay.jetty.handler;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.mortbay.jetty.Handler;
import org.mortbay.jetty.HandlerContainer;
import org.mortbay.jetty.HttpConnection;
import org.mortbay.jetty.Request;
import org.mortbay.jetty.servlet.PathMap;
import org.mortbay.log.Log;
import org.mortbay.util.LazyList;

/* ------------------------------------------------------------ */
/** ContextHandlerCollection.
 * 
 * This {@link org.mortbay.jetty.handler.HandlerCollection} is creates a 
 * {@link org.mortbay.jetty.servlet.PathMap} to it's contained handlers based
 * on the context path and virtual hosts of any contained {@link org.mortbay.jetty.handler.ContextHandler}s.
 * The contexts do not need to be directly contained, only children of the contained handlers.
 * Multiple contexts may have the same context path and they are called in order until one
 * handles the request.  
 * 
 * @org.apache.xbean.XBean element="contexts"
 */
public class ContextHandlerCollection extends HandlerCollection
{ 
    private PathMap _contextMap;
    private Class _contextClass = ContextHandler.class;
    
    /* ------------------------------------------------------------ */
    /**
     * Remap the context paths.
     */
    public void mapContexts()
    {
        PathMap contextMap = new PathMap();
        Handler[] branches = getHandlers();
        
        
        for (int b=0;branches!=null && b<branches.length;b++)
        {
            Handler[] handlers=null;
            
            if (branches[b] instanceof ContextHandler)
            {
                handlers = new Handler[]{ branches[b] };
            }
            else if (branches[b] instanceof HandlerContainer)
            {
                handlers = ((HandlerContainer)branches[b]).getChildHandlersByClass(ContextHandler.class);
            }
            else 
                continue;
            
            for (int i=0;i<handlers.length;i++)
            {
                ContextHandler handler=(ContextHandler)handlers[i];

                String contextPath=handler.getContextPath();

                if (contextPath==null || contextPath.indexOf(',')>=0 || contextPath.startsWith("*"))
                    throw new IllegalArgumentException ("Illegal context spec:"+contextPath);

                if(!contextPath.startsWith("/"))
                    contextPath='/'+contextPath;

                if (contextPath.length()>1)
                {
                    if (contextPath.endsWith("/"))
                        contextPath+="*";
                    else if (!contextPath.endsWith("/*"))
                        contextPath+="/*";
                }

                Object contexts=contextMap.get(contextPath);
                String[] vhosts=handler.getVirtualHosts();

                
                if (vhosts!=null && vhosts.length>0)
                {
                    Map hosts;

                    if (contexts instanceof Map)
                        hosts=(Map)contexts;
                    else
                    {
                        hosts=new HashMap(); 
                        hosts.put("*",contexts);
                        contextMap.put(contextPath, hosts);
                    }

                    for (int j=0;j<vhosts.length;j++)
                    {
                        String vhost=vhosts[j];
                        contexts=hosts.get(vhost);
                        contexts=LazyList.add(contexts,branches[b]);
                        hosts.put(vhost,contexts);
                    }
                }
                else if (contexts instanceof Map)
                {
                    Map hosts=(Map)contexts;
                    contexts=hosts.get("*");
                    contexts= LazyList.add(contexts, branches[b]);
                    hosts.put("*",contexts);
                }
                else
                {
                    contexts= LazyList.add(contexts, branches[b]);
                    contextMap.put(contextPath, contexts);
                }
            }
        }
        _contextMap=contextMap;

    }
    

    
    /* ------------------------------------------------------------ */
    /* 
     * @see org.mortbay.jetty.handler.HandlerCollection#setHandlers(org.mortbay.jetty.Handler[])
     */
    public void setHandlers(Handler[] handlers)
    {
        _contextMap=null;
        super.setHandlers(handlers);
        if (isStarted())
            mapContexts();
    }

    /* ------------------------------------------------------------ */
    protected void doStart() throws Exception
    {
        mapContexts();
        super.doStart();
    }
    

    /* ------------------------------------------------------------ */
    /* 
     * @see org.mortbay.jetty.Handler#handle(java.lang.String, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, int)
     */
    public void handle(String target, HttpServletRequest request, HttpServletResponse response, int dispatch) throws IOException, ServletException
    {
        Handler[] handlers = getHandlers();
        if (handlers==null || handlers.length==0)
	    return;

	Request base_request = HttpConnection.getCurrentConnection().getRequest();
	PathMap map = _contextMap;
	if (map!=null && target!=null && target.startsWith("/"))
	{
	    Object contexts = map.getLazyMatches(target);

            for (int i=0; i<LazyList.size(contexts); i++)
            {
                Map.Entry entry = (Map.Entry)LazyList.get(contexts, i);
                Object list = entry.getValue();

                if (list instanceof Map)
                {
                    Map hosts = (Map)list;
                    list=hosts.get(request.getServerName());
                    for (int j=0; j<LazyList.size(list); j++)
                    {
                        Handler handler = (Handler)LazyList.get(list,j);
                        handler.handle(target,request, response, dispatch);
                        if (base_request.isHandled())
                            return;
                    }
                    list=hosts.get("*");
                    for (int j=0; j<LazyList.size(list); j++)
                    {
                        Handler handler = (Handler)LazyList.get(list,j);
                        handler.handle(target,request, response, dispatch);
                        if (base_request.isHandled())
                            return;
                    }
                }
                else
                {
                    for (int j=0; j<LazyList.size(list); j++)
                    {
                        Handler handler = (Handler)LazyList.get(list,j);
                        handler.handle(target,request, response, dispatch);
                        if (base_request.isHandled())
                            return;
                    }
                }
	    }
	}
	else
	{
            // This may not work in all circumstances... but then I think it should never be called
	    for (int i=0;i<handlers.length;i++)
	    {
		handlers[i].handle(target,request, response, dispatch);
		if ( base_request.isHandled())
		    return;
	    }
	}
    }
    
    
    /* ------------------------------------------------------------ */
    /** Add a context handler.
     * @param contextPath  The context path to add
     * @return
     * @throws IllegalAccessException 
     * @throws InstantiationException 
     */
    public ContextHandler addContext(String contextPath,String resourceBase) 
    {
        try
        {
            ContextHandler context = (ContextHandler)_contextClass.newInstance();
            context.setContextPath(contextPath);
            context.setResourceBase(resourceBase);
            addHandler(context);
            return context;
        }
        catch (Exception e)
        {
            Log.warn(e);
            throw new Error(e);
        }
    }



    /* ------------------------------------------------------------ */
    /**
     * @return The class to use to add new Contexts
     */
    public Class getContextClass()
    {
        return _contextClass;
    }


    /* ------------------------------------------------------------ */
    /**
     * @param contextClass The class to use to add new Contexts
     */
    public void setContextClass(Class contextClass)
    {
        if (contextClass ==null || !(ContextHandler.class.isAssignableFrom(contextClass)))
            throw new IllegalArgumentException();
        _contextClass = contextClass;
    }
    
    
}