001// Copyright 2005 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.tapestry.request;
016
017import java.io.IOException;
018
019import javax.servlet.ServletException;
020import javax.servlet.http.HttpServletRequest;
021import javax.servlet.http.HttpServletResponse;
022
023import org.apache.tapestry.Tapestry;
024import org.apache.tapestry.services.ServletRequestServicer;
025import org.apache.tapestry.services.ServletRequestServicerFilter;
026import org.apache.tapestry.spec.ILibrarySpecification;
027
028/**
029 * Checks to see if a {@link org.apache.tapestry.request.IRequestDecoder}has been provided as an
030 * application extension, and (if so), creates a new HttpServletRequest wrapper around the decoded
031 * request.
032 * 
033 * @author Howard M. Lewis Ship
034 * @since 4.0
035 */
036public class DecodedRequestInjector implements ServletRequestServicerFilter
037{
038    private ILibrarySpecification _applicationSpecification;
039
040    private IRequestDecoder _decoder;
041
042    public void initializeService()
043    {
044        if (_applicationSpecification.checkExtension(Tapestry.REQUEST_DECODER_EXTENSION_NAME))
045            _decoder = (IRequestDecoder) _applicationSpecification.getExtension(
046                    Tapestry.REQUEST_DECODER_EXTENSION_NAME,
047                    IRequestDecoder.class);
048    }
049
050    public void service(HttpServletRequest request, HttpServletResponse response,
051            ServletRequestServicer servicer) throws IOException, ServletException
052    {
053        HttpServletRequest decodedRequest = _decoder == null ? request : wrapRequest(request);
054
055        servicer.service(decodedRequest, response);
056    }
057
058    public HttpServletRequest wrapRequest(HttpServletRequest request)
059    {
060        DecodedRequest decodedRequest = _decoder.decodeRequest(request);
061
062        return new DecodedRequestWrapper(request, decodedRequest);
063    }
064
065    public void setApplicationSpecification(ILibrarySpecification applicationSpecification)
066    {
067        _applicationSpecification = applicationSpecification;
068    }
069
070}