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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.apps.mailreader.actions;
22  
23  import java.util.Locale;
24  
25  import jakarta.servlet.http.HttpServletRequest;
26  import jakarta.servlet.http.HttpServletResponse;
27  import jakarta.servlet.http.HttpSession;
28  
29  import org.apache.struts.Globals;
30  import org.apache.struts.action.ActionForm;
31  import org.apache.struts.action.ActionForward;
32  import org.apache.struts.action.ActionMapping;
33  import org.slf4j.Logger;
34  import org.slf4j.LoggerFactory;
35  
36  
37  /**
38   * <p>
39   * Change user's Struts {@link java.util.Locale}.
40   * </p>
41   */
42  public final class LocaleAction extends BaseAction {
43      private static final long serialVersionUID = 7038993006910281561L;
44  
45      /**
46       * The {@code Log} instance for this class.
47       */
48      private final static Logger LOG =
49          LoggerFactory.getLogger(LocaleAction.class);
50  
51      /**
52       * <p>
53       * Return true if parameter is null or trims to empty.
54       * </p>
55       *
56       * @param string The string to text; may be  null
57       * @return true if parameter is null or empty
58       */
59      private boolean isBlank(String string) {
60          return ((string == null) || (string.trim().length() == 0));
61      }
62  
63      /**
64       * <p>
65       * Parameter for {@link java.util.Locale} language property. ["language"]
66       * </p>
67       */
68      private static final String LANGUAGE = "language";
69  
70      /**
71       * <p>
72       * Parameter for {@link java.util.Locale} country property. ["country"]
73       * </p>
74       */
75      private static final String COUNTRY = "country";
76  
77      /**
78       * <p>
79       * Parameter for response page URI. ["page"]
80       * </p>
81       */
82      private static final String PAGE = "page";
83  
84      /**
85       * <p>
86       * Parameter for response forward name. ["forward"]
87       * </p>
88       */
89      private static final String FORWARD = "forward";
90  
91      /**
92       * <p>
93       * Logging message if LocaleAction is missing a target parameter.
94       * </p>
95       */
96      private static final String LOCALE_LOG =
97              "LocaleAction: Missing page or forward parameter";
98  
99      /**
100      * <p>
101      * Change the user's Struts {@link java.util.Locale} based on request
102      * parameters for "language", "country".
103      * After setting the Locale, control is forwarded to an URI path
104      * indicated by a "page" parameter, or a forward indicated by a
105      * "forward" parameter, or to a forward given as the mappings
106      * "parameter" property.
107      * The response location must be specified one of these ways.
108      * </p>
109      *
110      * @param mapping  The ActionMapping used to select this instance
111      * @param form     The optional ActionForm bean for this request (if any)
112      * @param request  The HTTP request we are processing
113      * @param response The HTTP response we are creating
114      * @return An ActionForward indicate the resources that will render the
115      *         response
116      * @throws Exception if an input/output error or servlet exception occurs
117      */
118     public ActionForward execute(ActionMapping mapping,
119                                  ActionForm form,
120                                  HttpServletRequest request,
121                                  HttpServletResponse response)
122             throws Exception {
123 
124         String language = request.getParameter(LANGUAGE);
125         String country = request.getParameter(COUNTRY);
126 
127         Locale locale = getLocale(request);
128 
129         if ((!isBlank(language)) && (!isBlank(country))) {
130             locale = new Locale(language, country);
131         } else if (!isBlank(language)) {
132             locale = new Locale(language);
133         }
134 
135         HttpSession session = request.getSession();
136         session.setAttribute(Globals.LOCALE_KEY, locale);
137 
138         String target = request.getParameter(PAGE);
139         if (!isBlank(target)) {
140             return new ActionForward(target);
141         }
142 
143         target = request.getParameter(FORWARD);
144         if (isBlank(target)) {
145             target = mapping.getParameter();
146         }
147         if (isBlank(target)) {
148             LOG.warn(LOCALE_LOG);
149             return null;
150         }
151         return mapping.findForward(target);
152     }
153 }