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Java > Open Source Codes > org > apache > struts > webapp > example2 > SaveSubscriptionAction


1 /*
2  * Copyright 1999-2002,2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16
17
18 package org.apache.struts.webapp.example2;
19
20
21 import java.lang.reflect.InvocationTargetException JavaDoc;
22 import java.util.Locale JavaDoc;
23 import javax.servlet.ServletException JavaDoc;
24 import javax.servlet.http.HttpServletRequest JavaDoc;
25 import javax.servlet.http.HttpServletResponse JavaDoc;
26 import javax.servlet.http.HttpSession JavaDoc;
27 import org.apache.commons.beanutils.PropertyUtils;
28 import org.apache.commons.logging.Log;
29 import org.apache.commons.logging.LogFactory;
30 import org.apache.struts.action.Action;
31 import org.apache.struts.action.ActionForm;
32 import org.apache.struts.action.ActionForward;
33 import org.apache.struts.action.ActionMapping;
34 import org.apache.struts.util.MessageResources;
35
36
37 /**
38  * Implementation of <strong>Action</strong> that validates and creates or
39  * updates the mail subscription entered by the user.
40  *
41  * @author Craig R. McClanahan
42  * @version $Rev: 54936 $ $Date: 2004-10-16 18:57:09 +0100 (Sat, 16 Oct 2004) $
43  */
44
45 public final class SaveSubscriptionAction extends Action {
46
47
48     // ----------------------------------------------------- Instance Variables
49
50
51     /**
52      * The <code>Log</code> instance for this application.
53      */
54     private Log log =
55         LogFactory.getLog("org.apache.struts.webapp.Example");
56
57
58     // --------------------------------------------------------- Public Methods
59
60
61     /**
62      * Process the specified HTTP request, and create the corresponding HTTP
63      * response (or forward to another web component that will create it).
64      * Return an <code>ActionForward</code> instance describing where and how
65      * control should be forwarded, or <code>null</code> if the response has
66      * already been completed.
67      *
68      * @param mapping The ActionMapping used to select this instance
69      * @param form The optional ActionForm bean for this request (if any)
70      * @param request The HTTP request we are processing
71      * @param response The HTTP response we are creating
72      *
73      * @exception Exception if the application business logic throws
74      * an exception
75      */
76     public ActionForward execute(ActionMapping mapping,
77                  ActionForm form,
78                  HttpServletRequest JavaDoc request,
79                  HttpServletResponse JavaDoc response)
80     throws Exception JavaDoc {
81
82     // Extract attributes and parameters we will need
83 Locale JavaDoc locale = getLocale(request);
84     MessageResources messages = getResources(request);
85     HttpSession JavaDoc session = request.getSession();
86     SubscriptionForm subform = (SubscriptionForm) form;
87     String JavaDoc action = subform.getAction();
88     if (action == null) {
89         action = "?";
90         }
91         if (log.isDebugEnabled()) {
92             log.debug("SaveSubscriptionAction: Processing " + action +
93                       " action");
94         }
95
96     // Is there a currently logged on user?
97 User user = (User) session.getAttribute(Constants.USER_KEY);
98     if (user == null) {
99             if (log.isTraceEnabled()) {
100                 log.trace(" User is not logged on in session "
101                           + session.getId());
102             }
103         return (mapping.findForward("logon"));
104         }
105
106     // Was this transaction cancelled?
107 if (isCancelled(request)) {
108             if (log.isTraceEnabled()) {
109                 log.trace(" Transaction '" + action +
110                           "' was cancelled");
111             }
112             session.removeAttribute(Constants.SUBSCRIPTION_KEY);
113         return (mapping.findForward("success"));
114     }
115
116     // Is there a related Subscription object?
117 Subscription subscription =
118       (Subscription) session.getAttribute(Constants.SUBSCRIPTION_KEY);
119         if ("Create".equals(action)) {
120             if (log.isTraceEnabled()) {
121                 log.trace(" Creating subscription for mail server '" +
122                           subform.getHost() + "'");
123             }
124             subscription =
125                 user.createSubscription(subform.getHost());
126         }
127     if (subscription == null) {
128             if (log.isTraceEnabled()) {
129                 log.trace(" Missing subscription for user '" +
130                           user.getUsername() + "'");
131             }
132         response.sendError(HttpServletResponse.SC_BAD_REQUEST,
133                            messages.getMessage("error.noSubscription"));
134         return (null);
135     }
136
137     // Was this transaction a Delete?
138 if (action.equals("Delete")) {
139             if (log.isTraceEnabled()) {
140                 log.trace(" Deleting mail server '" +
141                           subscription.getHost() + "' for user '" +
142                           user.getUsername() + "'");
143             }
144             user.removeSubscription(subscription);
145         session.removeAttribute(Constants.SUBSCRIPTION_KEY);
146             try {
147                 UserDatabase database = (UserDatabase)
148                     servlet.getServletContext().
149                     getAttribute(Constants.DATABASE_KEY);
150                 database.save();
151             } catch (Exception JavaDoc e) {
152                 log.error("Database save", e);
153             }
154         return (mapping.findForward("success"));
155     }
156
157     // All required validations were done by the form itself
158
159     // Update the persistent subscription information
160 if (log.isTraceEnabled()) {
161             log.trace(" Populating database from form bean");
162         }
163         try {
164             PropertyUtils.copyProperties(subscription, subform);
165         } catch (InvocationTargetException JavaDoc e) {
166             Throwable JavaDoc t = e.getTargetException();
167             if (t == null)
168                 t = e;
169             log.error("Subscription.populate", t);
170             throw new ServletException JavaDoc("Subscription.populate", t);
171         } catch (Throwable JavaDoc t) {
172             log.error("Subscription.populate", t);
173             throw new ServletException JavaDoc("Subscription.populate", t);
174         }
175
176         try {
177             UserDatabase database = (UserDatabase)
178                 servlet.getServletContext().
179                 getAttribute(Constants.DATABASE_KEY);
180             database.save();
181         } catch (Exception JavaDoc e) {
182             log.error("Database save", e);
183         }
184
185     // Remove the obsolete form bean and current subscription
186 if (mapping.getAttribute() != null) {
187             if ("request".equals(mapping.getScope()))
188                 request.removeAttribute(mapping.getAttribute());
189             else
190                 session.removeAttribute(mapping.getAttribute());
191         }
192     session.removeAttribute(Constants.SUBSCRIPTION_KEY);
193
194     // Forward control to the specified success URI
195 if (log.isTraceEnabled()) {
196             log.trace(" Forwarding to success page");
197         }
198     return (mapping.findForward("success"));
199
200     }
201
202
203 }
204
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