001// Copyright 2007, 2008 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.internal.services;
016
017import org.apache.tapestry5.services.*;
018
019import java.io.IOException;
020
021/**
022 * A filter that intercepts Ajax-oriented requests, thos that originate on the client-side using XmlHttpRequest. In
023 * these cases, the action processing occurs normally, but the response is quite different.
024 */
025public class AjaxFilter implements ComponentEventRequestFilter
026{
027    private final Request request;
028
029    private final ComponentEventRequestHandler ajaxHandler;
030
031    public AjaxFilter(Request request, @Ajax ComponentEventRequestHandler ajaxHandler)
032    {
033        this.request = request;
034        this.ajaxHandler = ajaxHandler;
035    }
036
037    public void handle(ComponentEventRequestParameters parameters, ComponentEventRequestHandler handler)
038            throws IOException
039    {
040        ComponentEventRequestHandler next = request.isXHR() ? ajaxHandler : handler;
041
042        next.handle(parameters);
043    }
044
045}