1 /*
2 * $Id: PerformForward.java 471754 2006-11-06 14:55:09Z husted $
3 *
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21 package org.apache.struts.chain.commands.servlet;
22
23 import java.io.IOException;
24
25 import org.apache.commons.logging.Log;
26 import org.apache.commons.logging.LogFactory;
27 import org.apache.struts.action.ActionServlet;
28 import org.apache.struts.chain.commands.AbstractPerformForward;
29 import org.apache.struts.chain.contexts.ActionContext;
30 import org.apache.struts.chain.contexts.ServletActionContext;
31 import org.apache.struts.config.ForwardConfig;
32 import org.apache.struts.config.ModuleConfig;
33 import org.apache.struts.util.MessageResources;
34 import org.apache.struts.util.RequestUtils;
35 import org.apache.struts.util.ModuleUtils;
36
37 import javax.servlet.RequestDispatcher;
38 import javax.servlet.ServletContext;
39 import javax.servlet.ServletException;
40 import javax.servlet.http.HttpServletRequest;
41 import javax.servlet.http.HttpServletResponse;
42
43 /**
44 * <p>Perform forwarding or redirection based on the specified
45 * <code>ForwardConfig</code> (if any).</p>
46 *
47 * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $
48 */
49 public class PerformForward extends AbstractPerformForward {
50 private static final Log LOG = LogFactory.getLog(PerformForward.class);
51
52 // ------------------------------------------------------- Protected Methods
53
54 /**
55 * <p>Perform the appropriate processing on the specified
56 * <code>ForwardConfig</code>.</p>
57 *
58 * @param context The context for this request
59 * @param forwardConfig The forward to be performed
60 */
61 protected void perform(ActionContext context, ForwardConfig forwardConfig)
62 throws Exception {
63 ServletActionContext sacontext = (ServletActionContext) context;
64 String uri = forwardConfig.getPath();
65
66 if (uri == null) {
67 ActionServlet servlet = sacontext.getActionServlet();
68 MessageResources resources = servlet.getInternal();
69
70 throw new IllegalArgumentException(resources.getMessage("forwardPathNull"));
71 }
72
73 HttpServletRequest request = sacontext.getRequest();
74 ServletContext servletContext = sacontext.getContext();
75 HttpServletResponse response = sacontext.getResponse();
76
77 // If the forward can be unaliased into an action, then use the path of the action
78 String actionIdPath = RequestUtils.actionIdURL(forwardConfig, sacontext.getRequest(), sacontext.getActionServlet());
79 if (actionIdPath != null) {
80 uri = actionIdPath;
81 ForwardConfig actionIdForwardConfig = new ForwardConfig(forwardConfig);
82 actionIdForwardConfig.setPath(actionIdPath);
83 forwardConfig = actionIdForwardConfig;
84 }
85
86 if (uri.startsWith("/")) {
87 uri = resolveModuleRelativePath(forwardConfig, servletContext, request);
88 }
89
90
91 if (response.isCommitted() && !forwardConfig.getRedirect()) {
92 handleAsInclude(uri, servletContext, request, response);
93 } else if (forwardConfig.getRedirect()) {
94 handleAsRedirect(uri, request, response);
95 } else {
96 handleAsForward(uri, servletContext, request, response);
97 }
98 }
99
100 private String resolveModuleRelativePath(ForwardConfig forwardConfig, ServletContext servletContext, HttpServletRequest request) {
101 String prefix = forwardConfig.getModule();
102 ModuleConfig moduleConfig = ModuleUtils.getInstance().getModuleConfig(prefix, request, servletContext);
103 return RequestUtils.forwardURL(request,forwardConfig, moduleConfig);
104 }
105
106 private void handleAsForward(String uri, ServletContext servletContext, HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
107 RequestDispatcher rd = servletContext.getRequestDispatcher(uri);
108
109 if (LOG.isDebugEnabled()) {
110 LOG.debug("Forwarding to " + uri);
111 }
112
113 rd.forward(request, response);
114 }
115
116 private void handleAsRedirect(String uri, HttpServletRequest request, HttpServletResponse response) throws IOException {
117 if (uri.startsWith("/")) {
118 uri = request.getContextPath() + uri;
119 }
120
121 if (LOG.isDebugEnabled()) {
122 LOG.debug("Redirecting to " + uri);
123 }
124
125 response.sendRedirect(response.encodeRedirectURL(uri));
126 }
127
128 private void handleAsInclude(String uri, ServletContext servletContext, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
129 RequestDispatcher rd = servletContext.getRequestDispatcher(uri);
130
131 if (rd == null) {
132 response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR,
133 "Error getting RequestDispatcher for " + uri);
134 return;
135 }
136
137 if (LOG.isDebugEnabled()) {
138 LOG.debug("Including " + uri);
139 }
140
141 rd.include(request, response);
142 }
143 }
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