libjava/classpath/javax/swing/text/rtf/RTFParser.java

/* RTFParser.java --
   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
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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
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terms of your choice, provided that you also meet, for each linked
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package javax.swing.text.rtf;

import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;

import javax.swing.text.BadLocationException;
import javax.swing.text.Document;

/**
 * Parses an RTF file into a {@link Document}. The parser utilizes
 * {@link RTFScanner}.
 *
 * @author Roman Kennke (roman@ontographics.com)
 */
class RTFParser
{

  /**
   * Our scanner.
   */
  private RTFScanner scanner;

  /**
   * The document into which we parse.
   */
  private Document doc;

  /**
   * The current position.
   */
  private int pos;

  /**
   * Constructs a new RTFParser for the specified document and position,
   * without initializing the scanner. This is only used internally.
   *
   * @param doc the {@link Document} into which we should parse
   * @param pos the position to start
   */
  private RTFParser(Document doc, int pos)
  {
    this.doc = doc;
    this.pos = pos;
  }

  /**
   * Constructs a new RTFParser for the specified <code>stream</code>.
   *
   * @param stream the stream from which we parse
   * @param doc the {@link Document} into which we should parse
   * @param pos the position to start
   */
  public RTFParser(InputStream stream, Document doc, int pos)
  {
    this(doc, pos);
    scanner = new RTFScanner(stream);
  }

  /**
   * Constructs a new RTFParser for the specified <code>reader</code>.
   *
   * @param reader the reader from which we parse
   * @param doc the {@link Document} into which we should parse
   * @param pos the position to start
   */
  public RTFParser(Reader reader, Document doc, int pos)
  {
    this(doc, pos);
    scanner = new RTFScanner(reader);
  }

  /**
   * Returns the {@link Document} in which we parsed the RTF data.
   *
   * @return the {@link Document} in which we parsed the RTF data
   */
  public Document getDocument()
  {
    return doc;
  }

  /**
   * Starts the parsing process.
   */
  public void parse()
    throws IOException, BadLocationException
  {
    parseFile();
  }

  /**
   * The parse rules for &lt;file&gt;.
   */
  private void parseFile()
    throws IOException, BadLocationException
  {
    Token t1 = scanner.readToken();
    if (t1.type != Token.LCURLY)
      throw new RTFParseException("expected left curly braces");

    parseHeader();
    parseDocument();

    Token t2 = scanner.peekToken();
    if (t2.type == Token.RCURLY)
      {
        // Eat the token.
        scanner.readToken();
      }
    else
      {
        // Ignore this for maximum robustness when file is broken.
        System.err.println("RTF warning: expected right curly braces");
      }

  }

  /**
   * The parse rules for &lt;header&gt;.
   *
   * TODO: implement this properly
   */
  private void parseHeader()
  //throws IOException, BadLocationException
  {
    // TODO add parse rules here
  }


  /**
   * The parse rules for &lt;document&gt;.
   *
   * TODO: implement this properly
   */
  private void parseDocument()
    throws IOException, BadLocationException
  {
    //  !!! TODO !!!
    // This simply emits every TEXT Token as text to the document
    // which is plain stupid

    boolean eof = false;

    do {
      Token token = scanner.readToken();
      switch (token.type)
        {
        case Token.TEXT:
          TextToken textToken = (TextToken) token;
          doc.insertString(pos, textToken.text, null);
          pos += textToken.text.length();
          break;
        case Token.EOF:
          eof = true;
          break;
        default:
          // FIXME
          break;
        }
    } while (!eof);

  }

}