old-autovect-branch/libjava/classpath/javax/swing/text/html/parser/ParserDelegator.java

   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 import gnu.javax.swing.text.html.parser.htmlAttributeSet;
  42
  43 import java.io.IOException;
  44 import java.io.Reader;
  45 import java.io.Serializable;
  46
  47 import javax.swing.text.BadLocationException;
  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  * TODO Later this class must be derived from the totally abstract class
  56  * HTMLEditorKit.Parser. HTMLEditorKit that does not yet exist.
  57  *
  58  * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
  59  */
  60 public class ParserDelegator
  61   extends javax.swing.text.html.HTMLEditorKit.Parser
  62   implements Serializable
  63 {
  64   private class gnuParser
  65     extends gnu.javax.swing.text.html.parser.support.Parser
  66   {
  67     private static final long serialVersionUID = 1;
  68
  69     private gnuParser(DTD d)
  70     {
  71       super(d);
  72     }
  73
  74     protected final void handleComment(char[] comment)
  75     {
  76       callBack.handleComment(comment, hTag.where.startPosition);
  77     }
  78
  79     protected final void handleEmptyTag(TagElement tag)
  80       throws javax.swing.text.ChangedCharSetException
  81     {
  82       callBack.handleSimpleTag(tag.getHTMLTag(), getAttributes(),
  83                                hTag.where.startPosition
  84                               );
  85     }
  86
  87     protected final void handleEndTag(TagElement tag)
  88     {
  89       callBack.handleEndTag(tag.getHTMLTag(), hTag.where.startPosition);
  90     }
  91
  92     protected final void handleError(int line, String message)
  93     {
  94       callBack.handleError(message, hTag.where.startPosition);
  95     }
  96
  97     protected final void handleStartTag(TagElement tag)
  98     {
  99       htmlAttributeSet attributes = gnu.getAttributes();
 100
 101       if (tag.fictional())
 102         attributes.addAttribute(ParserCallback.IMPLIED, Boolean.TRUE);
 103
 104       callBack.handleStartTag(tag.getHTMLTag(), attributes,
 105                               hTag.where.startPosition
 106                              );
 107     }
 108
 109     protected final void handleText(char[] text)
 110     {
 111       callBack.handleText(text, hTag.where.startPosition);
 112     }
 113
 114     DTD getDTD()
 115     {
 116       // Accessing the inherited gnu.javax.swing.text.html.parser.support.Parser
 117       // field. super. is a workaround, required to support JDK1.3's javac.
 118       return super.dtd;
 119     }
 120   }
 121
 122   /**
 123    * Use serialVersionUID for interoperability.
 124    */
 125   private static final long serialVersionUID = -1276686502624777206L;
 126
 127   private static DTD dtd = HTML_401F.getInstance();
 128
 129   /**
 130    * The callback.
 131    * This is package-private to avoid an accessor method.
 132    */
 133   HTMLEditorKit.ParserCallback callBack;
 134
 135   /**
 136    * The reference to the working class of HTML parser that is
 137    * actually used to parse the document.
 138    * This is package-private to avoid an accessor method.
 139    */
 140   gnuParser gnu;
 141
 142   /**
 143    * Parses the HTML document, calling methods of the provided
 144    * callback. This method must be multithread - safe.
 145    * @param reader The reader to read the HTML document from
 146    * @param a_callback The callback that is notifyed about the presence
 147    * of HTML elements in the document.
 148    * @param ignoreCharSet If thrue, any charset changes during parsing
 149    * are ignored.
 150    * @throws java.io.IOException
 151    */
 152   public void parse(Reader reader, HTMLEditorKit.ParserCallback a_callback,
 153                     boolean ignoreCharSet
 154                    )
 155              throws IOException
 156   {
 157     callBack = a_callback;
 158
 159     if (gnu == null || !dtd.equals(gnu.getDTD()))
 160       {
 161         gnu = new gnuParser(dtd);
 162       }
 163
 164     gnu.parse(reader);
 165
 166     callBack.handleEndOfLineString(gnu.getEndOfLineSequence());
 167     try
 168       {
 169         callBack.flush();
 170       }
 171     catch (BadLocationException ex)
 172       {
 173         // Convert this into the supported type of exception.
 174         throw new IOException(ex.getMessage());
 175       }
 176   }
 177
 178   /**
 179    * Calling this method instructs that, if not specified directly,
 180    * the documents will be parsed using the default
 181    * DTD of the implementation.
 182    */
 183   protected static void setDefaultDTD()
 184   {
 185     dtd = HTML_401F.getInstance();
 186   }
 187
 188   /**
 189    * Registers the user - written DTD under the given name, also
 190    * making it default for the subsequent parsings. This has effect on
 191    * all subsequent calls to the parse(...) . If you need to specify
 192    * your DTD locally, simply {@link javax.swing.text.html.parser.Parser}
 193    * instead.
 194    * @param a_dtd The DTD that will be used to parse documents by this class.
 195    * @param name The name of this DTD.
 196    * @return No standard is specified on which instance of DTD must be
 197    * returned by this method, and it is recommended to leave the returned
 198    * value without consideration. This implementation returns the DTD
 199    * that was previously set as the default DTD, or the implementations
 200    * default DTD if none was set.
 201    */
 202   protected static DTD createDTD(DTD a_dtd, String name)
 203   {
 204     DTD.putDTDHash(name, a_dtd);
 205
 206     DTD dtd_prev = dtd;
 207     dtd = a_dtd;
 208     return dtd_prev;
 209   }
 210 }