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Java > Open Source Codes > org > apache > jetspeed > util > rewriter > SampleRewriter


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
17 package org.apache.jetspeed.util.rewriter;
18
19
20 // java.io
21 import java.io.Reader JavaDoc;
22
23 // java.net
24 import java.net.MalformedURLException JavaDoc;
25
26 // this makes it dependent on Swing...need an abstraction WTP
27 import javax.swing.text.html.HTML JavaDoc;
28 import javax.swing.text.MutableAttributeSet JavaDoc;
29
30 /**
31  *
32  * Sample of extending HTML Rewriter for your specific needs
33  *
34  *
35  * @author <a HREF="mailto:taylor@apache.org">David Sean Taylor</a>
36  * @version $Id: SampleRewriter.java,v 1.5 2004/02/23 03:18:59 jford Exp $
37  */
38
39 public class SampleRewriter extends HTMLRewriter
40 {
41     private boolean debug = false;
42     private String JavaDoc basePortalURL;
43     private String JavaDoc fullPortalURL;
44     private String JavaDoc sampleURL;
45
46     private String JavaDoc sessionID = "NONE";
47     private String JavaDoc formID = "NONE";
48     private boolean sampleEndFlag = false;
49
50     public String JavaDoc getSessionID()
51     {
52         return sessionID;
53     }
54
55     public String JavaDoc getFormID()
56     {
57         return formID;
58     }
59
60     public boolean getSampleEndFlag()
61     {
62         return sampleEndFlag;
63     }
64
65     /*
66      * Basic constructor for creating a Sample Rewriter.
67      *
68      * @param basePortalURL Base Portal URL
69      * @param fullPortalURL Full Portal URL with path parameters and query strings (sessionid)
70      * @param sampleURL The sample URL.
71      *
72      */
73     public SampleRewriter(String JavaDoc basePortalURL, String JavaDoc fullPortalURL, String JavaDoc sampleURL )
74     {
75         this.basePortalURL = basePortalURL;
76         this.fullPortalURL = fullPortalURL;
77         this.sampleURL = sampleURL;
78     }
79
80     /*
81      * Entry point into rewriting HTML content.
82      *
83      * Reads stream from proxied host, runs configured HTML parser against that stream,
84      * rewriting relevant links, and writes the parsed stream back to the client.
85      *
86      * @param input the HTML input stream.
87      * @param baseURL the base URL of the target host.
88      * @return the rewritten HTML output stream.
89      *
90      * @exception MalformedURLException a servlet exception.
91      */
92
93     public String JavaDoc rewrite(Reader JavaDoc input, String JavaDoc baseURL)
94                                throws MalformedURLException JavaDoc
95     {
96         String JavaDoc rewrittenHTML = "";
97         this.basePortalURL = baseURL;
98
99         HTMLParserAdaptor parser = new SwingParserAdaptor(this);
100         rewrittenHTML = parser.run(input);
101
102         return rewrittenHTML;
103     }
104
105     /*
106      * <p>
107      * This callback is called by the HTMLParserAdaptor implementation to write
108      * back all rewritten URLs to point to the proxy server. The MMS implementation
109      * writes specifically for network element ids and relative paths to MMS
110      * resources.
111      * </p>
112      * <p>
113      * Given the targetURL, rewrites the link as a link back to the proxy server.
114      * </p>
115      *
116      * Example format:
117      *
118      * http://proxyserver/proxy?neid=id?nepath=path
119      *
120      * @param targetURL the URL to be rewritten back to the proxy server.
121      * @param baseURL the base URL of the target host.
122      * @param proxyURL the base URL of the proxy server.
123      * @return the rewritten URL to the proxy server.
124      *
125      * @exception MalformedURLException a servlet exception.
126      */
127     public String JavaDoc generateNewUrl(String JavaDoc targetURL, HTML.Tag JavaDoc tag, HTML.Attribute JavaDoc attribute)
128     {
129         if (debug)
130             System.out.println("[rewriter] Tag: " + tag.toString() + " Attribute: " + attribute.toString() + " targetURL: " + targetURL + " target = " + fullPortalURL + "]");
131
132         // The only URL we want to re-write is ACTION attribute of the <FORM> tag.
133 // Ignore all others
134 if (tag == HTML.Tag.FORM && attribute == HTML.Attribute.ACTION) {
135
136             // Strip the session Id value out of the ACTION attribute value
137 int sessionLocation = targetURL.indexOf( "?sessionId" );
138             if (sessionLocation > -1) {
139                 int equalsLocation = targetURL.indexOf( "=", sessionLocation );
140                 if (equalsLocation > -1) {
141                     int ampLocation = targetURL.indexOf( "&", equalsLocation );
142                     if (ampLocation > -1) {
143                         sessionID = targetURL.substring( equalsLocation + 1, ampLocation );
144                     } else {
145                         sessionID = targetURL.substring( equalsLocation + 1 );
146                     }
147                 }
148             }
149
150             if (sampleEndFlag) {
151                 // The sample session is being terminated, make the form action return to the portal home page
152 return basePortalURL;
153             } else {
154                 // Make the form action run the same portal page
155 return fullPortalURL;
156             }
157         }
158
159         // This is a tag that we do not wish to re-write, return it's own value unmodified
160 return targetURL;
161     }
162
163     /*
164      * Returns true if all rewritten URLs should be sent back to the proxy server.
165      *
166      * @return true if all URLs are rewritten back to proxy server.
167      */
168     public boolean proxyAllTags()
169     {
170         return true;
171     }
172
173     /*
174      * Start Tag Events
175      */
176     public String JavaDoc exitStartTagEvent(HTML.Tag JavaDoc tag, MutableAttributeSet JavaDoc attrs)
177     {
178         if (tag == HTML.Tag.FORM)
179         {
180             String JavaDoc inputTag = "<input type='hidden' name='sessionId' value='" + sessionID + "'/>";
181             return inputTag;
182         }
183         return null;
184     }
185
186     /*
187      * Simple Tag Events
188      */
189
190     public boolean enterSimpleTagEvent(HTML.Tag JavaDoc tag, MutableAttributeSet JavaDoc attrs)
191     {
192         if (tag == HTML.Tag.META)
193         {
194             Object JavaDoc o = attrs.getAttribute(HTML.Attribute.NAME);
195             if (o != null)
196             {
197                 String JavaDoc s = o.toString();
198                 if (s.equalsIgnoreCase("SampleEnd"))
199                 {
200                     sampleEndFlag = true;
201                 }
202             }
203         }
204         return true;
205     }
206
207
208     /*
209      * Convert Tag Events
210      */
211
212     public void convertTagEvent(HTML.Tag JavaDoc tag, MutableAttributeSet JavaDoc attrs)
213     {
214         if (tag == HTML.Tag.FORM) {
215            // All forms from sample will have the same form NAME.
216 // Jetspeed will add its own FORM depending on the type of portlet
217 // being used. So if you have multiple forms, any Javascript will
218 // have to know which form to reference.
219 attrs.addAttribute("NAME","SampleForm");
220         }
221
222         // INPUT Tag
223 if (tag == HTML.Tag.INPUT)
224         {
225             Object JavaDoc o = attrs.getAttribute(HTML.Attribute.NAME);
226             if (o != null)
227             {
228                 String JavaDoc s = o.toString();
229                 if (s.equalsIgnoreCase("FormID"))
230                 {
231                     o = attrs.getAttribute(HTML.Attribute.VALUE);
232                     if (o != null)
233                     {
234                         formID = o.toString();
235                     }
236                 }
237             }
238         }
239
240     }
241
242 }
243
244
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