1 /*
2 * $Id$
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;
22
23 import java.util.Map;
24
25 import org.apache.struts.Globals;
26 import org.apache.struts.action.ActionMessages;
27 import org.apache.struts.chain.contexts.ActionContext;
28 import org.apache.struts.config.ForwardConfig;
29
30 /**
31 * Copies any <code>ActionMessages</code> from the request to the session if a
32 * redirecting forward is selected and the messages were not accessed. This
33 * allows messages to be retained across a redirect, and then later released by
34 * the <code>RemoveCachedMessages</code> command. The most common use case for
35 * this command is when the validator or exception handler places messages in
36 * the request.
37 *
38 * @version $Id$
39 * @see RemoveCachedMessages
40 * @since Struts 1.4.0
41 */
42 public class CacheMessages extends ActionCommandBase {
43
44 @Override
45 protected boolean execute_(ActionContext actionCtx) throws Exception {
46 ForwardConfig forwardConfig = actionCtx.getForwardConfig();
47 if ((forwardConfig != null) && forwardConfig.getRedirect()) {
48 Map<String, Object> request = actionCtx.getRequestScope();
49 Map<String, Object> session = actionCtx.getSessionScope();
50 copyUnaccessedMessages(request, session, Globals.MESSAGE_KEY);
51 copyUnaccessedMessages(request, session, Globals.ERROR_KEY);
52 }
53
54 return CONTINUE_PROCESSING;
55 }
56
57 /**
58 * Adds any <code>ActionMessages</code> object to the destination scope,
59 * stored under the specified key, if the messages were not accessed through
60 * the source scope.
61 *
62 * @param fromScope The scope to check for unacessed messages.
63 * @param toScope The scope to copy messages into.
64 * @param key The key the messages are stored under.
65 */
66 private void copyUnaccessedMessages(Map<String, Object> fromScope, Map<String, Object> toScope, String key) {
67 ActionMessages fromMessages = (ActionMessages) fromScope.get(key);
68 if ((fromMessages != null) && !fromMessages.isAccessed()) {
69 ActionMessages toMessages = (ActionMessages) toScope.get(key);
70 if (toMessages != null) {
71 toMessages.add(fromMessages);
72 } else {
73 toScope.put(key, fromMessages);
74 }
75 }
76 }
77 }