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1
16
17 package org.apache.jetspeed.portal.portlets;
18
19 import java.io.IOException  ;
21 import java.io.Reader ;
22 import java.io.StringReader ;
23 import java.util.Enumeration ;
24 import java.util.Hashtable ;
25 import java.util.Iterator ;
26
27 import org.apache.jetspeed.util.JetspeedClearElement;
29 import org.apache.ecs.ConcreteElement;
30
31 import org.apache.jetspeed.util.MimeType;
33 import org.apache.jetspeed.util.SimpleTransform;
34 import org.apache.jetspeed.cache.disk.JetspeedDiskCache;
35 import org.apache.jetspeed.portal.PortletException;
36 import org.apache.jetspeed.xml.JetspeedXMLEntityResolver;
37 import org.apache.jetspeed.capability.CapabilityMap;
38 import org.apache.jetspeed.capability.CapabilityMapFactory;
39 import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
40 import org.apache.jetspeed.services.logging.JetspeedLogger;
41 import org.apache.jetspeed.services.rundata.JetspeedRunData;
42
43 import org.apache.turbine.util.RunData;
45
46 import javax.xml.parsers.DocumentBuilder ;
48 import javax.xml.parsers.DocumentBuilderFactory ;
49
50 import org.w3c.dom.Document ;
52 import org.w3c.dom.Node ;
53 import org.w3c.dom.NodeList ;
54 import org.xml.sax.InputSource ;
55 import org.xml.sax.SAXException ;
56
57
77 public class NewRSSPortlet extends FileWatchPortlet
78 {
79
80
83 private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(NewRSSPortlet.class.getName());
84
85 public final static String ERROR_NOT_VALID = "This does not appear to be an RSS document";
86 public final static String INVALID_TYPE = "Unable to display for this browser";
87
88 private Document document = null;
89 private Hashtable stylesheets = null;
90 private Hashtable params = null;
91
92
96 public void init( ) throws PortletException {
97
98 super.init();
100
101 DocumentBuilder parser = null;
102 String url = null;
103
104 stylesheets = new Hashtable ();
106 params = new Hashtable ();
107 Iterator i = this.getPortletConfig().getInitParameterNames();
108 while (i.hasNext()) {
109 String name = (String )i.next();
110 String base = MimeType.HTML.toString();
111
112 if (name.startsWith("stylesheet")) {
113 int idx=-1;
114 if ((idx=name.indexOf("."))>-1) {
115 base= name.substring(idx+1,name.length());
116 }
117 stylesheets.put(base, getPortletConfig().getInitParameter(name));
118 } else {
119 params.put(name.toLowerCase(), getPortletConfig().getInitParameter(name));
120 }
121 }
122
123 try
125 {
126 final DocumentBuilderFactory docfactory = DocumentBuilderFactory.newInstance();
127 docfactory.setValidating(false);
129 parser= docfactory.newDocumentBuilder();
130 parser.setEntityResolver(new JetspeedXMLEntityResolver() );
131
132 url = getPortletConfig().getURL();
133 String content = JetspeedDiskCache.getInstance().getEntry( url ).getData();
134 CapabilityMap xmap =
135 CapabilityMapFactory.getCapabilityMap(CapabilityMapFactory.AGENT_XML);
136 setContent( new JetspeedClearElement(content), xmap );
137 InputSource isrc = new InputSource ( this.cleanse( content ) );
138 isrc.setSystemId( url );
139 isrc.setEncoding("UTF-8");
140 this.document = parser.parse( isrc );
141 this.setMetainfo(document);
142
143 } catch ( Throwable t )
144 {
145
146 String message = "RSSPortlet: Couldn't parse out XML document -> " +
147 url;
148
149 logger.error( message, t );
150 throw new PortletException( t.getMessage() );
151 }
152
153
154 }
155
156
161 private void setMetainfo(Document document) throws PortletException
162 {
163 String title = null;
165 String description = null;
166
167 Node channel = null;
169
170 NodeList list = document.getElementsByTagName( "channel" );
171
172 if ( list.getLength() != 1 ) {
173 throw new PortletException( ERROR_NOT_VALID );
174 }
175
176 channel = list.item( 0 );
177
178 Node tn = getNode( channel, "title" );
179
180 if ( tn == null ) {
181 throw new PortletException( ERROR_NOT_VALID );
182 }
183 else
184 {
185 Node fc = tn.getFirstChild();
186 if (fc != null)
187 {
188 title = fc.getNodeValue();
189 }
190 }
191
192 Node dn = getNode( channel, "description" );
193
194 if ( dn != null )
195 {
196 Node fc = dn.getFirstChild();
197 if (fc != null)
198 {
199 description = fc.getNodeValue();
200 }
201 }
202
203 this.setTitle( title );
204 this.setDescription( description );
205 }
206
207
214 public ConcreteElement getContent( RunData data )
215 {
216 if (org.apache.jetspeed.util.PortletSessionState.getPortletConfigChanged(this, data))
217 {
218 try
219 {
220 init();
221 }
222 catch (PortletException pe)
223 {
224 logger.error("Exception", pe);
225 }
226 }
227 CapabilityMap map = ((JetspeedRunData)data).getCapability();
228 String type = map.getPreferredType().toString();
229 ConcreteElement content = new JetspeedClearElement(INVALID_TYPE);
230 String stylesheet = (String )stylesheets.get(type);
231
232 if (stylesheet != null) {
233 content = getContent( data, map );
234 if ( content == null ) {
235 try {
236 content = new JetspeedClearElement(
237 SimpleTransform.transform( this.document,
238 stylesheet,
239 this.params ) );
240 setContent( content, map );
241 } catch ( SAXException e ) {
242 logger.error("Exception", e);
243 content = new JetspeedClearElement(e.getMessage());
244 }
245 }
246 }
247 else
248 {
249 if (map.getPreferredType().equals(MimeType.XML))
250 {
251 return getContent( data, map );
252 }
253 }
254
255 return content;
256 }
257
258
267 public boolean supportsType( MimeType mimeType ) {
268
269 Enumeration en = stylesheets.keys();
270 while(en.hasMoreElements()) {
271 String type = (String )en.nextElement();
272 if (type.equals(mimeType.toString())) return true;
273 }
274
275 return false;
276 }
277
278
287 private final Node getNode( Node start, String name ) {
288
289 NodeList list = start.getChildNodes();
290
291 for ( int i = 0; i < list.getLength(); ++i ) {
292
293 Node node = list.item( i );
294
295 if ( node.getNodeName().equals( name ) ) {
296 return node;
297 }
298 }
299 return null;
300 }
301
302
314 private Reader cleanse( String content ) throws IOException {
315
316 String filtered = null;
317
318 String XMLDECL = "<?xml version=";
321
322 int start = content.indexOf( XMLDECL );
323
324 if ( start <= 0 ) {
325 filtered = content;
326 } else {
327 filtered = content.substring( start, content.length() );
328 }
329
330 return new StringReader ( filtered );
331 }
332
333 }
334
335 |
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