001    /**
002     * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portal.kernel.servlet;
016    
017    import com.liferay.portal.kernel.util.GetterUtil;
018    import com.liferay.portal.kernel.util.ObjectValuePair;
019    
020    import java.util.Enumeration;
021    
022    import javax.servlet.RequestDispatcher;
023    import javax.servlet.http.HttpServletRequest;
024    import javax.servlet.http.HttpServletRequestWrapper;
025    import javax.servlet.http.HttpServletResponse;
026    
027    /**
028     * @author Shuyang Zhou
029     */
030    public class RequestDispatcherUtil {
031    
032            public static ObjectValuePair<String, Long> getContentAndLastModifiedTime(
033                            RequestDispatcher requestDispatcher, HttpServletRequest request,
034                            HttpServletResponse response)
035                    throws Exception {
036    
037                    BufferCacheServletResponse bufferCacheServletResponse =
038                            new BufferCacheServletResponse(response);
039    
040                    requestDispatcher.include(
041                            new HttpServletRequestWrapper(request) {
042    
043                                    @Override
044                                    public long getDateHeader(String name) {
045                                            if (name.equals(HttpHeaders.IF_MODIFIED_SINCE)) {
046                                                    return -1;
047                                            }
048    
049                                            return super.getDateHeader(name);
050                                    }
051    
052                                    @Override
053                                    public String getHeader(String name) {
054                                            if (name.equals(HttpHeaders.IF_MODIFIED_SINCE) ||
055                                                    name.equals(HttpHeaders.IF_NONE_MATCH) ||
056                                                    name.equals(HttpHeaders.LAST_MODIFIED)) {
057    
058                                                    return null;
059                                            }
060    
061                                            return super.getHeader(name);
062                                    }
063    
064                                    @Override
065                                    public Enumeration<String> getHeaders(String name) {
066                                            if (name.equals(HttpHeaders.IF_MODIFIED_SINCE) ||
067                                                    name.equals(HttpHeaders.IF_NONE_MATCH) ||
068                                                    name.equals(HttpHeaders.LAST_MODIFIED)) {
069    
070                                                    return null;
071                                            }
072    
073                                            return super.getHeaders(name);
074                                    }
075    
076                                    @Override
077                                    public String getMethod() {
078                                            return HttpMethods.GET;
079                                    }
080    
081                            }, bufferCacheServletResponse);
082    
083                    return new ObjectValuePair<>(
084                            bufferCacheServletResponse.getString(),
085                            GetterUtil.getLong(
086                                    bufferCacheServletResponse.getHeader(HttpHeaders.LAST_MODIFIED),
087                                    -1));
088            }
089    
090            public static long getLastModifiedTime(
091                            RequestDispatcher requestDispatcher, HttpServletRequest request,
092                            HttpServletResponse response)
093                    throws Exception {
094    
095                    MetaInfoCacheServletResponse metaInfoCacheServletResponse =
096                            new MetaInfoCacheServletResponse(response);
097    
098                    requestDispatcher.include(
099                            new HttpServletRequestWrapper(request) {
100    
101                                    @Override
102                                    public String getMethod() {
103                                            return HttpMethods.HEAD;
104                                    }
105    
106                            }, metaInfoCacheServletResponse);
107    
108                    return GetterUtil.getLong(
109                            metaInfoCacheServletResponse.getHeader(HttpHeaders.LAST_MODIFIED),
110                            -1);
111            }
112    
113    }