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1   /*
2    * Copyright 2000-2001,2004 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  package org.apache.jetspeed.portal.portlets.viewprocessor;
17  
18  // Jetspeed apis
19  import org.apache.jetspeed.portal.Portlet;
20  import org.apache.jetspeed.portal.PortletException;
21  
22  // XML stuff
23  import org.w3c.dom.Node;
24  import org.w3c.dom.NodeList;
25  
26  /***
27   * <p>Portlet which renders RDF Site Summary.</p>
28   * <p>This portlet uses XML stylesheet for transforming the RSS
29   * content into display markup depending on the MimeType requested
30   * by the user-agent</p>
31   * <p>It accepts the following parameters :
32   * <dl>
33   * <dt>itemDisplayed</dt>
34   * <dd>The number of items from the RSS file to display on screen. Default 15 for HTML, 5 for WML</dd>
35   * <dt>showDescription</dt>
36   * <dd>Should the portlet show the item descriptions. Must be true or false. Default: true for HTML, false for WML</dd>
37   * <dt>showTitle</dt>
38   * <dd>Should the portlet show the channel description. Must be true or false. Default: true for HTML, false for WML</dd>
39   * <dt>stylesheet[.<mime>]</dt>
40   * <dd>The stylesheet URL. If a mime-type is specified, the stylesheet
41   * is only used for this mime-type</dd>
42   * </dl>
43   * 
44   * @author <A HREF="mailto:raphael@apache.org">RaphaŽl Luta</A>
45   * @version $Id: $
46   * @since 1.4b4
47   */
48  public class RSSViewProcessor extends XSLViewProcessor
49  {
50  
51      /***
52       * This method loads the init parameters and
53       * parse the document tied to this portlet
54       * 
55       * @param portlet
56       * @exception PortletException
57       */
58      public void init(Portlet portlet)
59      throws PortletException
60      {
61  
62          super.init(portlet);
63  
64          //Determine title and description for this portlet
65          String title = null;
66          String description = null;
67  
68          //now find the channel node.
69          Node channel = null;
70          NodeList list = this.document.getElementsByTagName("channel");
71  
72          if (list.getLength() != 1)
73          {
74              throw new PortletException(ERROR_NOT_VALID);
75          }
76  
77          channel = list.item(0);
78  
79          Node tn = getNode( channel, "title" );
80  
81          if ( tn == null ) {
82              throw new PortletException( ERROR_NOT_VALID );
83          } 
84          else 
85          {
86              Node fc = tn.getFirstChild();
87              if (fc != null)
88              {
89                  title = fc.getNodeValue();
90              }
91          }
92  
93          Node dn = getNode( channel, "description" );
94  
95          if ( dn != null ) 
96          {
97              Node fc = dn.getFirstChild();
98              if (fc != null)
99              {
100                 description = fc.getNodeValue();
101             }
102         }
103 
104         portlet.setTitle(title);
105         portlet.setDescription(description);
106     }
107 
108 }