1 /* ParserDelegator.java -- Delegator for ParserDocument.
2     Copyright (C) 2005 Free Software Foundation, Inc.
3 
4 This file is part of GNU Classpath.
5 
6 GNU Classpath is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10 
11 GNU Classpath is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GNU Classpath; see the file COPYING.  If not, write to the
18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 02110-1301 USA.
20 
21 Linking this library statically or dynamically with other modules is
22 making a combined work based on this library.  Thus, the terms and
23 conditions of the GNU General Public License cover the whole
24 combination.
25 
26 As a special exception, the copyright holders of this library give you
27 permission to link this library with independent modules to produce an
28 executable, regardless of the license terms of these independent
29 modules, and to copy and distribute the resulting executable under
30 terms of your choice, provided that you also meet, for each linked
31 independent module, the terms and conditions of the license of that
32 module.  An independent module is a module which is not derived from
33 or based on this library.  If you modify this library, you may extend
34 this exception to your version of the library, but you are not
35 obligated to do so.  If you do not wish to do so, delete this
36 exception statement from your version. */
37 
38 package javax.swing.text.html.parser;
39 
40 import gnu.javax.swing.text.html.parser.HTML_401F;
41 
42 import java.io.IOException;
43 import java.io.Reader;
44 import java.io.Serializable;
45 
46 import javax.swing.text.BadLocationException;
47 import javax.swing.text.SimpleAttributeSet;
48 import javax.swing.text.html.HTMLEditorKit;
49 import javax.swing.text.html.HTMLEditorKit.ParserCallback;
50 
51 /**
52  * This class instantiates and starts the working instance of
53  * html parser, being responsible for providing the default DTD.
54  *
55  * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
56  */
57 public class ParserDelegator
58   extends javax.swing.text.html.HTMLEditorKit.Parser
59   implements Serializable
60 {
61   private class gnuParser
62     extends gnu.javax.swing.text.html.parser.support.Parser
63   {
64     private static final long serialVersionUID = 1;
65 
gnuParser(DTD d)66     private gnuParser(DTD d)
67     {
68       super(d);
69     }
70 
handleComment(char[] comment)71     protected final void handleComment(char[] comment)
72     {
73       callBack.handleComment(comment, hTag.where.startPosition);
74     }
75 
handleEmptyTag(TagElement tag)76     protected final void handleEmptyTag(TagElement tag)
77       throws javax.swing.text.ChangedCharSetException
78     {
79       callBack.handleSimpleTag(tag.getHTMLTag(), getAttributes(),
80                                hTag.where.startPosition
81                               );
82     }
83 
handleEndTag(TagElement tag)84     protected final void handleEndTag(TagElement tag)
85     {
86       callBack.handleEndTag(tag.getHTMLTag(), hTag.where.startPosition);
87     }
88 
handleError(int line, String message)89     protected final void handleError(int line, String message)
90     {
91       callBack.handleError(message, hTag.where.startPosition);
92     }
93 
handleStartTag(TagElement tag)94     protected final void handleStartTag(TagElement tag)
95     {
96       SimpleAttributeSet attributes = gnu.getAttributes();
97 
98       if (tag.fictional())
99         attributes.addAttribute(ParserCallback.IMPLIED, Boolean.TRUE);
100 
101       callBack.handleStartTag(tag.getHTMLTag(), attributes,
102                               hTag.where.startPosition
103                              );
104     }
105 
handleText(char[] text)106     protected final void handleText(char[] text)
107     {
108       callBack.handleText(text, hTag.where.startPosition);
109     }
110 
getDTD()111     DTD getDTD()
112     {
113       // Accessing the inherited gnu.javax.swing.text.html.parser.support.Parser
114       // field. super. is a workaround, required to support JDK1.3's javac.
115       return super.dtd;
116     }
117   }
118 
119   /**
120    * Use serialVersionUID for interoperability.
121    */
122   private static final long serialVersionUID = -1276686502624777206L;
123 
124   private static DTD dtd = HTML_401F.getInstance();
125 
126   /**
127    * The callback.
128    * This is package-private to avoid an accessor method.
129    */
130   HTMLEditorKit.ParserCallback callBack;
131 
132   /**
133    * The reference to the working class of HTML parser that is
134    * actually used to parse the document.
135    * This is package-private to avoid an accessor method.
136    */
137   gnuParser gnu;
138 
139   /**
140    * Parses the HTML document, calling methods of the provided
141    * callback. This method must be multithread - safe.
142    * @param reader The reader to read the HTML document from
143    * @param a_callback The callback that is notifyed about the presence
144    * of HTML elements in the document.
145    * @param ignoreCharSet If thrue, any charset changes during parsing
146    * are ignored.
147    * @throws java.io.IOException
148    */
parse(Reader reader, HTMLEditorKit.ParserCallback a_callback, boolean ignoreCharSet )149   public void parse(Reader reader, HTMLEditorKit.ParserCallback a_callback,
150                     boolean ignoreCharSet
151                    )
152              throws IOException
153   {
154     callBack = a_callback;
155 
156     if (gnu == null || !dtd.equals(gnu.getDTD()))
157       {
158         gnu = new gnuParser(dtd);
159       }
160 
161     gnu.parse(reader);
162 
163     callBack.handleEndOfLineString(gnu.getEndOfLineSequence());
164     try
165       {
166         callBack.flush();
167       }
168     catch (BadLocationException ex)
169       {
170         // Convert this into the supported type of exception.
171         throw new IOException(ex.getMessage());
172       }
173   }
174 
175   /**
176    * Calling this method instructs that, if not specified directly,
177    * the documents will be parsed using the default
178    * DTD of the implementation.
179    */
setDefaultDTD()180   protected static void setDefaultDTD()
181   {
182     dtd = HTML_401F.getInstance();
183   }
184 
185   /**
186    * Registers the user - written DTD under the given name, also
187    * making it default for the subsequent parsings. This has effect on
188    * all subsequent calls to the parse(...) . If you need to specify
189    * your DTD locally, simply {@link javax.swing.text.html.parser.Parser}
190    * instead.
191    * @param a_dtd The DTD that will be used to parse documents by this class.
192    * @param name The name of this DTD.
193    * @return No standard is specified on which instance of DTD must be
194    * returned by this method, and it is recommended to leave the returned
195    * value without consideration. This implementation returns the DTD
196    * that was previously set as the default DTD, or the implementations
197    * default DTD if none was set.
198    */
createDTD(DTD a_dtd, String name)199   protected static DTD createDTD(DTD a_dtd, String name)
200   {
201     DTD.putDTDHash(name, a_dtd);
202 
203     DTD dtd_prev = dtd;
204     dtd = a_dtd;
205     return dtd_prev;
206   }
207 }
208