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1   /*
2    * Copyright 2000-2004 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  package org.apache.jetspeed.portal.portlets;
18  
19  //Element Construction Set
20  import org.apache.ecs.ConcreteElement;
21  
22  //Jetspeed stuff
23  import org.apache.jetspeed.portal.PortletConfig;
24  import org.apache.jetspeed.portal.PortletException;
25  import org.apache.jetspeed.util.JetspeedClearElement;
26  import org.apache.jetspeed.util.SimpleTransform;
27  import org.apache.jetspeed.cache.disk.JetspeedDiskCache;
28  import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
29  import org.apache.jetspeed.services.logging.JetspeedLogger;
30  import org.apache.jetspeed.services.resources.JetspeedResources;
31  
32  
33  //XML stuff
34  import org.xml.sax.SAXException;
35  
36  //java stuff
37  import java.io.IOException;
38  
39  
40  /***
41  Provides a content publication system (like Slashdot).
42  
43  @author <a href="mailto:burton@apache.org">Kevin A. Burton</a>
44  @version $Id: JetspeedContent.java,v 1.26 2004/02/23 04:03:34 jford Exp $ 
45  */
46  public class JetspeedContent extends FileWatchPortlet 
47  {
48  
49      /***
50       * Static initialization of the logger for this class
51       */    
52      private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(JetspeedContent.class.getName());
53      
54      public static final String PROVIDER_NAME_KEY = "provider-name";
55  
56      /***
57      The name of the JPC provider.
58      */
59      private String provider = "";
60  
61      /***
62      The stylesheet for using with this provider
63      */
64      private String stylesheet = "";
65  
66      /***
67      The url that was specified by the provider
68      */
69      private String url = null;
70      
71      /***
72      Return the last time the provider's URL has been changed.
73      */
74      private long lastModified;
75      
76      
77      /***
78      Init this Portlet, set it's title, description, etc.
79      */
80      public void init() throws PortletException {
81  
82          PortletConfig config = this.getPortletConfig();
83          
84          provider = config.getInitParameter( PROVIDER_NAME_KEY );
85          
86          if ( provider == null ) {
87              throw new PortletException( "You need to specify " + PROVIDER_NAME_KEY );
88          }
89  
90          //NOTE:  There are no HARD keys here in JetspeedResources.  If you change
91          //this format of this it will break at runtime.  CAREFULL!
92          
93          this.url = JetspeedResources.getString( "content.provider." + provider + ".url" );
94          
95          this.stylesheet = JetspeedResources.getString( "content.provider." + provider + ".stylesheet.url" );
96          
97          String title = JetspeedResources.getString( "content.provider." + provider + ".title" );
98  
99          String description = JetspeedResources.getString( "content.provider." + provider + ".description" );
100 
101         this.setTitle( title );
102         this.setDescription( description );
103        
104         this.setContent( this.parse( url ) );
105             
106         //now make sure all the above 4 values are define within JetspeedResources
107         if ( url == null ||
108              stylesheet == null ||
109              title == null ||
110              description == null ) {
111             throw new PortletException( "Not all properties defined in JetspeedResources.  See JetspeedResources.properties notes." );
112         }
113         
114         this.getPortletConfig().setURL( url );
115         
116         //set the last modification date for this file so that if it is 
117         //modified this portlet can be expired from the cache.
118         
119         try {
120             this.lastModified = JetspeedDiskCache.getInstance()
121                 .getEntry( this.url ).getLastModified();
122         } catch ( IOException e ) {
123             logger.error("Exception",  e);
124         }
125         
126     }
127     
128     /***
129     Parse out the JCP URL and return it as a concrete element
130     */
131     private ConcreteElement parse( String url ) throws PortletException {
132  
133             
134         //now get the url and stylesheet from the JetspeedDiskCache store...
135 
136         try {
137         
138         url = JetspeedDiskCache.getInstance()
139             .getEntry( url ).getURL();
140 
141         this.stylesheet = JetspeedDiskCache.getInstance()
142             .getEntry( this.stylesheet ).getURL();
143         } catch (IOException e) {
144             logger.error( "Couldn't transform content.", e );
145             throw new PortletException( "Couldn't transform content.  Please see error log" );
146         }
147 
148         
149         try {
150             
151             return new JetspeedClearElement( SimpleTransform.transform( url, stylesheet ) );
152             
153         } catch (SAXException e) {
154             logger.error( "Couldn't transform content.", e );
155             throw new PortletException( "Couldn't transform content.  Please see error log" );
156         }
157 
158        
159     }
160     
161 }