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1   /*
2    * $Id: SaveSubscriptionAction.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  
22  
23  package org.apache.struts.webapp.example2;
24  
25  
26  import java.lang.reflect.InvocationTargetException;
27  import javax.servlet.ServletException;
28  import javax.servlet.http.HttpServletRequest;
29  import javax.servlet.http.HttpServletResponse;
30  import javax.servlet.http.HttpSession;
31  import org.apache.commons.beanutils.PropertyUtils;
32  import org.apache.commons.logging.Log;
33  import org.apache.commons.logging.LogFactory;
34  import org.apache.struts.action.Action;
35  import org.apache.struts.action.ActionForm;
36  import org.apache.struts.action.ActionForward;
37  import org.apache.struts.action.ActionMapping;
38  import org.apache.struts.util.MessageResources;
39  
40  
41  /**
42   * Implementation of <strong>Action</strong> that validates and creates or
43   * updates the mail subscription entered by the user.
44   *
45   * @author Craig R. McClanahan
46   * @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $
47   */
48  
49  public final class SaveSubscriptionAction extends Action {
50  
51  
52      // ----------------------------------------------------- Instance Variables
53  
54  
55      /**
56       * The <code>Log</code> instance for this application.
57       */
58      private Log log =
59          LogFactory.getLog("org.apache.struts.webapp.Example");
60  
61  
62      // --------------------------------------------------------- Public Methods
63  
64  
65      /**
66       * Process the specified HTTP request, and create the corresponding HTTP
67       * response (or forward to another web component that will create it).
68       * Return an <code>ActionForward</code> instance describing where and how
69       * control should be forwarded, or <code>null</code> if the response has
70       * already been completed.
71       *
72       * @param mapping The ActionMapping used to select this instance
73       * @param form The optional ActionForm bean for this request (if any)
74       * @param request The HTTP request we are processing
75       * @param response The HTTP response we are creating
76       *
77       * @exception Exception if the application business logic throws
78       *  an exception
79       */
80      public ActionForward execute(ActionMapping mapping,
81                   ActionForm form,
82                   HttpServletRequest request,
83                   HttpServletResponse response)
84      throws Exception {
85  
86      // Extract attributes and parameters we will need
87      MessageResources messages = getResources(request);
88      HttpSession session = request.getSession();
89      SubscriptionForm subform = (SubscriptionForm) form;
90      String action = subform.getAction();
91      if (action == null) {
92          action = "?";
93          }
94          if (log.isDebugEnabled()) {
95              log.debug("SaveSubscriptionAction:  Processing " + action +
96                        " action");
97          }
98  
99      // Is there a currently logged on user?
100     User user = (User) session.getAttribute(Constants.USER_KEY);
101     if (user == null) {
102             if (log.isTraceEnabled()) {
103                 log.trace(" User is not logged on in session "
104                           + session.getId());
105             }
106         return (mapping.findForward("logon"));
107         }
108 
109     // Was this transaction cancelled?
110     if (isCancelled(request)) {
111             if (log.isTraceEnabled()) {
112                 log.trace(" Transaction '" + action +
113                           "' was cancelled");
114             }
115             session.removeAttribute(Constants.SUBSCRIPTION_KEY);
116         return (mapping.findForward("success"));
117     }
118 
119     // Is there a related Subscription object?
120     Subscription subscription =
121       (Subscription) session.getAttribute(Constants.SUBSCRIPTION_KEY);
122         if ("Create".equals(action)) {
123             if (log.isTraceEnabled()) {
124                 log.trace(" Creating subscription for mail server '" +
125                           subform.getHost() + "'");
126             }
127             subscription =
128                 user.createSubscription(subform.getHost());
129         }
130     if (subscription == null) {
131             if (log.isTraceEnabled()) {
132                 log.trace(" Missing subscription for user '" +
133                           user.getUsername() + "'");
134             }
135         response.sendError(HttpServletResponse.SC_BAD_REQUEST,
136                            messages.getMessage("error.noSubscription"));
137         return (null);
138     }
139 
140     // Was this transaction a Delete?
141     if (action.equals("Delete")) {
142             if (log.isTraceEnabled()) {
143                 log.trace(" Deleting mail server '" +
144                           subscription.getHost() + "' for user '" +
145                           user.getUsername() + "'");
146             }
147             user.removeSubscription(subscription);
148         session.removeAttribute(Constants.SUBSCRIPTION_KEY);
149             try {
150                 UserDatabase database = (UserDatabase)
151                     servlet.getServletContext().
152                     getAttribute(Constants.DATABASE_KEY);
153                 database.save();
154             } catch (Exception e) {
155                 log.error("Database save", e);
156             }
157         return (mapping.findForward("success"));
158     }
159 
160     // All required validations were done by the form itself
161 
162     // Update the persistent subscription information
163         if (log.isTraceEnabled()) {
164             log.trace(" Populating database from form bean");
165         }
166         try {
167             PropertyUtils.copyProperties(subscription, subform);
168         } catch (InvocationTargetException e) {
169             Throwable t = e.getTargetException();
170             if (t == null)
171                 t = e;
172             log.error("Subscription.populate", t);
173             throw new ServletException("Subscription.populate", t);
174         } catch (Throwable t) {
175             log.error("Subscription.populate", t);
176             throw new ServletException("Subscription.populate", t);
177         }
178 
179         try {
180             UserDatabase database = (UserDatabase)
181                 servlet.getServletContext().
182                 getAttribute(Constants.DATABASE_KEY);
183             database.save();
184         } catch (Exception e) {
185             log.error("Database save", e);
186         }
187 
188     // Remove the obsolete form bean and current subscription
189     if (mapping.getAttribute() != null) {
190             if ("request".equals(mapping.getScope()))
191                 request.removeAttribute(mapping.getAttribute());
192             else
193                 session.removeAttribute(mapping.getAttribute());
194         }
195     session.removeAttribute(Constants.SUBSCRIPTION_KEY);
196 
197     // Forward control to the specified success URI
198         if (log.isTraceEnabled()) {
199             log.trace(" Forwarding to success page");
200         }
201     return (mapping.findForward("success"));
202 
203     }
204 
205 
206 }