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 org.apache.struts.Globals;
24 import org.apache.struts.chain.contexts.ActionContext;
25 import org.apache.struts.config.ModuleConfig;
26 import org.apache.struts.util.MessageResources;
27
28 /**
29 * <p>Cache the <code>ModuleConfig</code> and <code>MessageResources</code>
30 * instances for the sub-application module to be used for processing this
31 * request.</p>
32 *
33 * @version $Rev$ $Date: 2005-11-12 13:01:44 -0500 (Sat, 12 Nov 2005)
34 * $
35 */
36 public abstract class AbstractSelectModule extends ActionCommandBase {
37 // ------------------------------------------------------ Instance Variables
38 // ---------------------------------------------------------- Public Methods
39
40 /**
41 * <p>Cache the <code>ModuleConfig</code> and <code>MessageResources</code>
42 * instances for the sub-application module to be used for processing this
43 * request.</p>
44 *
45 * @param actionCtx The <code>Context</code> for the current request
46 * @return <code>false</code> so that processing continues
47 * @throws IllegalArgumentException if no valid ModuleConfig or
48 * MessageResources can be identified for
49 * this request
50 * @throws Exception if thrown by the Action class
51 */
52 @Override
53 protected boolean execute_(ActionContext actionCtx)
54 throws Exception {
55 String prefix = getPrefix(actionCtx);
56
57 // Cache the corresponding ModuleConfig and MessageResources instances
58 ModuleConfig moduleConfig =
59 (ModuleConfig) actionCtx.getApplicationScope().get(Globals.MODULE_KEY
60 + prefix);
61
62 if (moduleConfig == null) {
63 throw new IllegalArgumentException("No module config for prefix '"
64 + prefix + "'");
65 }
66
67 actionCtx.setModuleConfig(moduleConfig);
68
69 String key = Globals.MESSAGES_KEY + prefix;
70 MessageResources messageResources =
71 (MessageResources) actionCtx.getApplicationScope().get(key);
72
73 if (messageResources == null) {
74 throw new IllegalArgumentException(
75 "No message resources found in application scope under " + key);
76 }
77
78 actionCtx.setMessageResources(messageResources);
79
80 return CONTINUE_PROCESSING;
81 }
82
83 // ------------------------------------------------------- Protected Methods
84
85 /**
86 * <p>Calculate and return the module prefix for the module to be selected
87 * for this request.</p>
88 *
89 * @param context The <code>Context</code> for this request
90 * @return Module prefix to be used with this request
91 * @throws IllegalArgumentException if no valid ModuleConfig or
92 * MessageResources can be identified for
93 * this request
94 */
95 protected abstract String getPrefix(ActionContext context);
96 }