diff options
Diffstat (limited to 'libjava/classpath/javax/swing/text/html/parser/DocumentParser.java')
| -rw-r--r-- | libjava/classpath/javax/swing/text/html/parser/DocumentParser.java | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/libjava/classpath/javax/swing/text/html/parser/DocumentParser.java b/libjava/classpath/javax/swing/text/html/parser/DocumentParser.java new file mode 100644 index 000000000..f717d69cb --- /dev/null +++ b/libjava/classpath/javax/swing/text/html/parser/DocumentParser.java @@ -0,0 +1,268 @@ +/* DocumentParser.java -- A parser for HTML documents. + Copyright (C) 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package javax.swing.text.html.parser; + +import javax.swing.text.html.parser.Parser; + +import java.io.IOException; +import java.io.Reader; + +import javax.swing.text.BadLocationException; +import javax.swing.text.SimpleAttributeSet; +import javax.swing.text.html.HTMLEditorKit; + +/** + * <p>A simple error-tolerant HTML parser that uses a DTD document + * to access data on the possible tokens, arguments and syntax.</p> + * <p> The parser reads an HTML content from a Reader and calls various + * notifying methods (which should be overridden in a subclass) + * when tags or data are encountered.</p> + * <p>Some HTML elements need no opening or closing tags. The + * task of this parser is to invoke the tag handling methods also when + * the tags are not explicitly specified and must be supposed using + * information, stored in the DTD. + * For example, parsing the document + * <p><table><tr><td>a<td>b<td>c</tr> <br> + * will invoke exactly the handling methods exactly in the same order + * (and with the same parameters) as if parsing the document: <br> + * <em><html><head></head><body><table>< + * tbody></em><tr><td>a<em></td></em><td>b<em> + * </td></em><td>c<em></td></tr></em>< + * <em>/tbody></table></body></html></em></p> + * (supposed tags are given in italics). The parser also supports + * obsolete elements of HTML syntax.<p> + * </p> + * In this implementation, DocumentParser is directly derived from its + * ancestor without changes of functionality. + * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org) + */ +public class DocumentParser + extends Parser + implements DTDConstants +{ + /** + * The enclosed working parser class. + */ + private class gnuParser + extends gnu.javax.swing.text.html.parser.support.Parser + { + private gnuParser(DTD d) + { + super(d); + } + + protected final void handleComment(char[] comment) + { + parser.handleComment(comment); + callBack.handleComment(comment, hTag.where.startPosition); + } + + protected final void handleEmptyTag(TagElement tag) + throws javax.swing.text.ChangedCharSetException + { + parser.handleEmptyTag(tag); + callBack.handleSimpleTag(tag.getHTMLTag(), getAttributes(), + hTag.where.startPosition + ); + } + + protected final void handleEndTag(TagElement tag) + { + parser.handleEndTag(tag); + callBack.handleEndTag(tag.getHTMLTag(), hTag.where.startPosition); + } + + protected final void handleError(int line, String message) + { + parser.handleError(line, message); + callBack.handleError(message, hTag.where.startPosition); + } + + protected final void handleStartTag(TagElement tag) + { + parser.handleStartTag(tag); + SimpleAttributeSet attributes = gnu.getAttributes(); + + if (tag.fictional()) + attributes.addAttribute(HTMLEditorKit.ParserCallback.IMPLIED, + Boolean.TRUE + ); + + callBack.handleStartTag(tag.getHTMLTag(), attributes, + hTag.where.startPosition + ); + } + + protected final void handleText(char[] text) + { + parser.handleText(text); + callBack.handleText(text, hTag.where.startPosition); + } + + DTD getDTD() + { + return dtd; + } + } + + /** + * This field is used to access the identically named + * methods of the outer class. + * This is package-private to avoid an accessor method. + */ + DocumentParser parser = this; + + /** + * The callback. + * This is package-private to avoid an accessor method. + */ + HTMLEditorKit.ParserCallback callBack; + + /** + * The reference to the working class of HTML parser that is + * actually used to parse the document. + * This is package-private to avoid an accessor method. + */ + gnuParser gnu; + + /** + * Creates a new parser that uses the given DTD to access data on the + * possible tokens, arguments and syntax. There is no single - step way + * to get a default DTD; you must either refer to the implementation - + * specific packages, write your own DTD or obtain the working instance + * of parser in other way, for example, by calling + * {@link javax.swing.text.html.HTMLEditorKit#getParser()}. + * + * @param a_dtd a DTD to use. + */ + public DocumentParser(DTD a_dtd) + { + super(a_dtd); + gnu = new gnuParser(a_dtd); + } + + /** + * Parses the HTML document, calling methods of the provided + * callback. This method must be multithread - safe. + * @param reader The reader to read the HTML document from + * @param aCallback The callback that is notifyed about the presence + * of HTML elements in the document. + * @param ignoreCharSet If thrue, any charset changes during parsing + * are ignored. + * @throws java.io.IOException + */ + public void parse(Reader reader, HTMLEditorKit.ParserCallback aCallback, + boolean ignoreCharSet + ) + throws IOException + { + callBack = aCallback; + gnu.parse(reader); + + callBack.handleEndOfLineString(gnu.getEndOfLineSequence()); + try + { + callBack.flush(); + } + catch (BadLocationException ex) + { + // Convert this into the supported type of exception. + throw new IOException(ex.getMessage()); + } + } + + /** + * Handle HTML comment. The default method returns without action. + * @param comment the comment being handled + */ + protected void handleComment(char[] comment) + { + // This default implementation does nothing. + } + + /** + * Handle the tag with no content, like <br>. The method is + * called for the elements that, in accordance with the current DTD, + * has an empty content. + * @param tag the tag being handled. + * @throws javax.swing.text.ChangedCharSetException + */ + protected void handleEmptyTag(TagElement tag) + throws javax.swing.text.ChangedCharSetException + { + // This default implementation does nothing. + } + + /** + * The method is called when the HTML closing tag ((like </table>) + * is found or if the parser concludes that the one should be present + * in the current position. + * @param tag The tag being handled + */ + protected void handleEndTag(TagElement tag) + { + // This default implementation does nothing. + } + + /* Handle error that has occured in the given line. */ + protected void handleError(int line, String message) + { + // This default implementation does nothing. + } + + /** + * The method is called when the HTML opening tag ((like <table>) + * is found or if the parser concludes that the one should be present + * in the current position. + * @param tag The tag being handled + */ + protected void handleStartTag(TagElement tag) + { + // This default implementation does nothing. + } + + /** + * Handle the text section. + * @param text a section text. + */ + protected void handleText(char[] text) + { + // This default implementation does nothing. + } +} |