MessageTag


1   /*
2    * Copyright (c) 2003 - 2007 OpenSubsystems s.r.o. Slovak Republic. All rights reserved.
3    * 
4    * Project: OpenSubsystems
5    * 
6    * $Id: MessageTag.java,v 1.10 2007/01/07 06:14:09 bastafidli Exp $
7    * 
8    * This program is free software; you can redistribute it and/or modify
9    * it under the terms of the GNU General Public License as published by
10   * the Free Software Foundation; version 2 of the License. 
11   * 
12   * This program is distributed in the hope that it will be useful,
13   * but WITHOUT ANY WARRANTY; without even the implied warranty of
14   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   * GNU General Public License for more details.
16   * 
17   * You should have received a copy of the GNU General Public License
18   * along with this program; if not, write to the Free Software
19   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
20   */
21   
22  package org.opensubsystems.core.www;
23  
24  import java.util.Iterator  ;
25  import java.util.List  ;
26  
27  import javax.servlet.jsp.JspException  ;
28  import javax.servlet.jsp.tagext.TagSupport  ;
29  
30  import org.opensubsystems.core.util.Messages;
31  
32  /**
33   * Custom tag to display messages defined using call to 
34   * CallContext.getInstance().getMessages().addXYZ() on the UI processed using
35   * servlet derived from WebUIServlet. Place this tag in your JSP page at the 
36   * place where you want to display informational or error messages generated by 
37   * application for the user. This tag will generate DIV element with informational 
38   * and error messages in it that you can format using CSS. The default css classes 
39   * for this tag are included in &lt;%=contextpath%&gt;/core/css/message.css. 
40   * If you do not specify your own css styles, you should include this default 
41   * css file whenever you use this tag.
42   *  
43   * @version $Id: MessageTag.java,v 1.10 2007/01/07 06:14:09 bastafidli Exp $
44   * @author Miro Halas
45   * @code.reviewer Miro Halas
46   * @code.reviewed 1.7 2006/02/17 06:54:09 bastafidli
47   */
48  public class MessageTag extends TagSupport  
49  {
50     // Constants ////////////////////////////////////////////////////////////////
51  
52     /**
53      * Messages collected during processing of current request.
54      */
55     public static final String   MESSAGES_REQUEST_PARAM = "messages";
56     
57     // Attributes ///////////////////////////////////////////////////////////////
58     
59     /**
60      * Generated serial version id for this class.
61      */
62     private static final long serialVersionUID = 9202964907351336679L;
63  
64     /**
65      * Id of the DIV where messages will be displayed. Subarea where error 
66      * messages are displayed will have id created by appending error and subarea 
67      * for information messages will have id created by appending info. Required.
68      */
69     protected String   m_strId; 
70     
71     /**
72      * Class for the message labels.
73      */
74     protected String   m_strCssclass;
75     
76     /**
77      * Flag signaling to also include the message area if the area would be empty.
78      * If the message area should be included even if it is empty this should say 
79      * true or 1.
80      */
81     protected String   m_strEmpty;
82  
83     // Constructors /////////////////////////////////////////////////////////////
84     
85     /**
86      * Constructor for custom tag.
87      */
88     public MessageTag() 
89     {
90        super();
91        
92        m_strId = ""; 
93        m_strCssclass = "clsMessages";
94     }
95     
96     // Business logic ///////////////////////////////////////////////////////////
97     
98     /**
99      * {@inheritDoc}
100     */
101    public int doStartTag(
102    ) throws JspException   
103    {
104       Messages msgs = (Messages)pageContext.getRequest().getAttribute(
105                           MessageTag.MESSAGES_REQUEST_PARAM);
106       
107       if ((msgs != null) || (isEmptyArea()))
108       {                           
109          List   lstErrors = null;
110          List   lstInfos = null;
111          boolean bErrors;
112          boolean bInfo;
113          
114          if (msgs != null)
115          {
116             lstErrors = msgs.getAllErrorMessages();
117             lstInfos = msgs.getInfoMessages();
118          }
119          bErrors = ((lstErrors != null) && (!lstErrors.isEmpty()));
120          bInfo = ((lstInfos != null) && (!lstInfos.isEmpty()));
121 
122          if ((bErrors) || (bInfo) || (isEmptyArea()))
123          {
124             Iterator       iterator;
125             String         strMessage;
126             StringBuffer   sbHtml = null;
127             
128             sbHtml = new StringBuffer  ();
129             sbHtml.append("<div id=\"");
130             sbHtml.append(m_strId);
131             sbHtml.append("\"");
132             if ((m_strCssclass != null) && (m_strCssclass.length() > 0))
133             {
134                sbHtml.append(" class=\"");
135                sbHtml.append(m_strCssclass);
136                if ((msgs == null) 
137                   || (((lstErrors == null) || (lstErrors.isEmpty()))
138                   && ((lstInfos == null) || (lstInfos.isEmpty()))))
139                {
140                   sbHtml.append("Empty");                  
141                }
142                sbHtml.append("\"");
143             }
144             sbHtml.append(">");
145 
146             if ((bErrors) || (isEmptyArea())) 
147             {
148                sbHtml.append("<div id=\"");
149                sbHtml.append(m_strId);
150                sbHtml.append("error\"");
151                if ((m_strCssclass != null) && (m_strCssclass.length() > 0))
152                {
153                   sbHtml.append(" class=\"");
154                   sbHtml.append(m_strCssclass);
155                   sbHtml.append("Error\"");
156                }
157                sbHtml.append(">");
158                
159                if (lstErrors != null)
160                {
161                   for (iterator = lstErrors.iterator(); iterator.hasNext();)
162                   {
163                      strMessage = (String  ) iterator.next();
164                      sbHtml.append("<div>");
165                      sbHtml.append(strMessage);
166                      sbHtml.append("</div>\n");               
167                   }
168                }
169                
170                sbHtml.append("</div>\n");
171             }
172             if ((bInfo) || (isEmptyArea()))
173             {
174                sbHtml.append("<div id=\"");
175                sbHtml.append(m_strId);
176                sbHtml.append("info\"");
177                if ((m_strCssclass != null) && (m_strCssclass.length() > 0))
178                {
179                   sbHtml.append(" class=\"");
180                   sbHtml.append(m_strCssclass);
181                   sbHtml.append("Info\"");
182                }
183                sbHtml.append(">");
184                
185                if (lstInfos != null)
186                {
187                   for (iterator = lstInfos.iterator(); iterator.hasNext();)
188                   {
189                      strMessage = (String  ) iterator.next();
190                      sbHtml.append("<div>");
191                      sbHtml.append(strMessage);
192                      sbHtml.append("</div>\n");               
193                   }
194                }
195                
196                sbHtml.append("</div>\n");
197             }
198             sbHtml.append("</div>\n");
199             TagUtils.write(pageContext, sbHtml.toString());
200          }
201       }
202       
203       return (SKIP_BODY);
204    }
205 
206    /**
207     * {@inheritDoc}
208     */
209    public int doEndTag(
210    ) throws JspException   
211    {
212       return (EVAL_PAGE);
213    }
214 
215    /**
216     * @return String - Id of the DIV where messages will be displayed. Subarea
217     *                  where error messages are displayed will have id created
218     *                  by appending error and subarea for information messages 
219     *                  will have id created by appending info.
220     */
221    public String   getId(
222    )
223    {
224       return m_strId;
225    }
226 
227    /**
228     * @return String - CSS class for the area where messages are displayed. 
229     *                  Subarea where error messages are displayed will have class 
230     *                  created by appending Error and subarea for information 
231     *                  messages will have class created by appending Info
232     */
233    public String   getCssclass(
234    )
235    {
236       return m_strCssclass;
237    }
238 
239    /**
240     * @param string - Id of the DIV where messages will be displayed. Subarea
241     *                 where error messages are displayed will have id created
242     *                 by appending error and subarea for information messages 
243     *                 will have id created by appending info.
244     */
245    public void setId(
246       String   string
247    )
248    {
249       m_strId = string;
250    }
251 
252    /**
253     * @param string - CSS class for the area where messages are displayed. 
254     *                  Subarea where error messages are displayed will have class 
255     *                  created by appending Error and subarea for information 
256     *                  messages will have class created by appending Info.
257     */
258    public void setCssclass(String   string)
259    {
260       m_strCssclass = string;
261    }
262 
263    /**
264     * @return String - If the message area should be included even if it is empty 
265     *                  this should say true or 1.
266     */
267    public String   getEmpty(
268    )
269    {
270       return m_strEmpty;
271    }
272 
273    /**
274     * @param strEmpty - If the message area should be included even if it is empty 
275     *                  this should say true or 1.
276     */
277    public void setEmpty(
278       String   strEmpty
279    )
280    {
281       m_strEmpty = strEmpty;
282    }
283    
284    /**
285     * @param bEmpty - If the message area should be included even if it is empty 
286     *                 this should say true or 1.
287     */
288    public void setEmpty(
289       boolean bEmpty
290    )
291    {
292       m_strEmpty = Boolean.toString(bEmpty);
293    }
294 
295    /**
296     * @return boolean - true if the message area should be included even if empty
297     */
298    public boolean isEmptyArea(
299    )
300    {
301       return ((Boolean.TRUE.toString().equalsIgnoreCase(m_strEmpty))
302              || ("1".equals(m_strEmpty))); 
303    }
304 }
305
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