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Java > Open Source Codes > org > apache > jetspeed > portal > portlets > WebPagePortlet2


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.jetspeed.util.JetspeedClearElement;
21 import org.apache.ecs.ConcreteElement;
22
23 //Jetspeed stuff
24 import org.apache.jetspeed.portal.PortletConfig;
25 import org.apache.jetspeed.portal.PortletException;
26 import org.apache.jetspeed.services.logging.JetspeedLogFactoryService;
27 import org.apache.jetspeed.services.logging.JetspeedLogger;
28 import org.apache.jetspeed.util.rewriter.Rewriter;
29 import org.apache.jetspeed.util.rewriter.HTMLRewriter;
30 import org.apache.jetspeed.util.Base64;
31 import org.apache.jetspeed.util.template.JetspeedLink;
32 import org.apache.jetspeed.util.template.JetspeedLinkFactory;
33
34 //turbine
35 import org.apache.turbine.util.RunData;
36
37 //standard java stuff
38 import java.io.InputStreamReader JavaDoc;
39 import java.io.IOException JavaDoc;
40 import java.io.Reader JavaDoc;
41 import java.net.URL JavaDoc;
42 import java.net.URLConnection JavaDoc;
43
44 /**
45  * A class that loads a web page and filters it to have certain features
46  * deleted.
47  *
48  * @author <a HREF="mailto:taylor@apache.org">David Sean Taylor</a>
49  */
50 public class WebPagePortlet2 extends AbstractInstancePortlet
51 {
52
53     /**
54      * Static initialization of the logger for this class
55      */
56     private static final JetspeedLogger logger = JetspeedLogFactoryService.getLogger(WebPagePortlet2.class.getName());
57     
58     protected Rewriter rewriter = null;
59     protected boolean initDone = false;
60     protected boolean contentStale = true;
61     protected boolean cacheContent = false;
62     protected String JavaDoc username = null;
63     protected String JavaDoc password = null;
64     
65     /**
66      * Initialize this portlet by defining a HTML rewriter.
67      * @throws PortletException Initialization failed
68      */
69     public void init() throws PortletException
70     {
71   
72         if (initDone) // Why is init called more than once per portlet?
73 return;
74
75         PortletConfig config = this.getPortletConfig();
76         
77         try
78         {
79             rewriter = new HTMLRewriter();
80
81             // fetch username and password for HTTP Basic Autentication
82 username = config.getInitParameter("username");
83             password = config.getInitParameter("password");
84             
85             contentStale = true;
86             initDone = true;
87         }
88         catch (Exception JavaDoc e)
89         {
90             logger.info("Exception occurred:" + e.toString(), e);
91             throw new PortletException( e.toString() );
92         }
93     }
94     
95     /**
96      * took this from FileServerPortlet as it was private
97      *
98     */
99
100     // FIXME: Currently only the expiration the HTTP Response header is honored.
101 // Expiration information in <meta> tags are not honored
102
103     protected Reader JavaDoc getReader(String JavaDoc url) throws IOException JavaDoc
104     {
105         URL JavaDoc pageUrl = new URL JavaDoc(url);
106
107         URLConnection JavaDoc pageConn = pageUrl.openConnection();
108         try
109         {
110             // set HTTP Basic Authetication header if username and password are set
111 if (username != null && password !=null)
112             {
113                 pageConn.setRequestProperty("Authorization", "Basic " +
114                                         Base64.encodeAsString(username + ":" + password));
115             }
116                 
117         }
118         catch (Exception JavaDoc e)
119         {
120             logger.info("Exception occurred:" + e.toString(), e);
121         }
122         
123         long pageExpiration = pageConn.getExpiration();
124         String JavaDoc encoding = pageConn.getContentEncoding();
125         String JavaDoc tempString = null;
126         String JavaDoc noCache = "no-cache";
127         
128         if(encoding == null)
129         {
130             // Standard HTTP encoding
131 encoding = "iso-8859-1";
132         }
133
134         /*
135          * Determing if content should be cached.
136          */
137         cacheContent = true; // Assume content is cached
138 if (pageExpiration == 0)
139         {
140             cacheContent = false;
141         }
142         // Check header field CacheControl
143 tempString = pageConn.getHeaderField( "Cache-Control");
144         if (tempString != null)
145          {
146             if (tempString.toLowerCase().indexOf(noCache) >= 0)
147             {
148                 cacheContent = false;
149             }
150         }
151         // Check header field Pragma
152 tempString = pageConn.getHeaderField( "Pragma");
153         if (tempString != null)
154         {
155             if (tempString.toLowerCase().indexOf(noCache) >= 0)
156             {
157                 cacheContent = false;
158             }
159         }
160             
161         // Assign a reader
162 Reader JavaDoc rdr = new InputStreamReader JavaDoc(pageConn.getInputStream(),
163                                            encoding );
164
165         // Only set the page expiration it the page has not expired
166 if (pageExpiration > System.currentTimeMillis() && (cacheContent == true))
167         {
168             contentStale = false;
169             if ( logger.isDebugEnabled() )
170             {
171                 logger.debug( "WebPagePortlet caching URL: " +
172                        url +
173                        " Expiration: " +
174                        pageExpiration +
175                        ", " +
176                        (pageExpiration - System.currentTimeMillis() ) +
177                        " milliseconds into the future" );
178             }
179             setExpirationMillis(pageExpiration);
180         }
181         else
182         {
183             contentStale = true;
184         }
185
186         return rdr;
187     }
188
189
190     /**
191     This methods outputs the content of the portlet for a given
192     request.
193
194     @param data the RunData object for the request
195     @return the content to be displayed to the user-agent
196     */
197     public ConcreteElement getContent( RunData data )
198     {
199         PortletConfig config = this.getPortletConfig();
200         
201         if (contentStale == true)
202             return getWebPageContent(data, config);
203         
204         if (null == getExpirationMillis())
205             return getContent( data, null, true);
206         
207         if (getExpirationMillis().longValue() <= System.currentTimeMillis())
208             return getWebPageContent(data, config);
209
210         return getContent( data, null , true );
211     }
212
213     private ConcreteElement getWebPageContent( RunData data, PortletConfig config )
214     {
215         
216         String JavaDoc convertedString = null; // parsed and re-written HTML
217 JetspeedClearElement element = null;
218
219         String JavaDoc url = selectUrl( data, config );
220
221         try
222         {
223             JetspeedLink jsLink = JetspeedLinkFactory.getInstance(data);
224             Reader JavaDoc htmlReader = getReader( url );
225             convertedString = rewriter.rewrite(htmlReader, jsLink.toString());
226             element = new JetspeedClearElement(convertedString);
227             
228             System.out.println("js link = " + jsLink.toString());
229             JetspeedLinkFactory.putInstance(jsLink);
230
231             //FIXME: We should do a clearContent() for the media type, not ALL media types
232 this.clearContent(); // doing this because setContent() is not overwriting current content.
233 this.setContent(element);
234
235             htmlReader.close();
236         }
237         catch (Exception JavaDoc e)
238         {
239             logger.info("Exception occurred:" + e.toString(), e);
240         }
241
242         return element;
243     }
244     
245     /**
246      * Usually called by caching system when portlet is marked as expired, but
247      * has not be idle longer then TimeToLive.
248      *
249      * Any cached content that is expired need to be refreshed.
250      */
251     public void refresh()
252     {
253         if (cacheContent == true)
254         {
255           getWebPageContent(null, this.getPortletConfig());
256         }
257     }
258
259     /**
260     * Select the URL to use for this portlet.
261     * @return The URL to use for this portlet
262     */
263     protected String JavaDoc selectUrl( RunData data, PortletConfig config )
264     {
265         String JavaDoc url = config.getURL();
266
267         return url;
268
269     } // selectUrl
270
271 }
272
273
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