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.dispatcher.servlet;
22
23 import org.apache.struts.action.ActionMapping;
24 import org.apache.struts.chain.contexts.ActionContext;
25 import org.apache.struts.chain.contexts.ServletActionContext;
26 import org.apache.struts.dispatcher.AbstractEventMappingDispatcher;
27
28 import jakarta.servlet.http.HttpServletRequest;
29
30 /**
31 * This servlet-based dispatcher chooses the target method based on the
32 * <code>parameter</code> attribute of the {@link ActionMapping} that matches
33 * a submission parameter. This is useful for developers who prefer to use many
34 * submit buttons, images, or submit links on a single form and whose related
35 * actions exist in a single action.
36 * <p>
37 * To configure the use of this action in your configuration, create an entry
38 * like this:
39 *
40 * <pre><code>
41 * <action path="/saveSubscription"
42 * type="org.example.SubscriptionAction"
43 * dispatcher="org.apache.struts.dispatcher.servlet.ServletEventMappingDispatcher"/>
44 * parameter="save,back,recalc=recalculate,default=save"/>
45 * name="subscriptionForm"
46 * scope="request"
47 * input="/subscription.jsp"
48 * </code></pre>
49 *
50 * where <code>parameter</code> contains three possible methods and one
51 * default method if nothing matches (such as the user pressing the enter key).
52 *
53 * @version $Rev$
54 * @since Struts 1.4
55 */
56 public class ServletEventMappingDispatcher extends AbstractEventMappingDispatcher {
57
58 private static final long serialVersionUID = 1L;
59
60 /**
61 * Constructs a new servlet event mapping dispatcher.
62 */
63 public ServletEventMappingDispatcher() {
64 super(new ServletMethodResolver());
65 }
66
67 /**
68 * If the method key exists as a standalone parameter or with the image
69 * suffixes (.x/.y), the method name has been found.
70 */
71 protected boolean isSubmissionParameter(ActionContext context, String methodKey) {
72 HttpServletRequest request = ((ServletActionContext) context).getRequest();
73 return (request.getParameter(methodKey) != null) || (request.getParameter(methodKey + ".x") != null);
74 }
75
76 }