Source for java.text.Bidi

   1: /* Bidi.java -- Bidirectional Algorithm implementation
   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: 
  39: package java.text;
  40: 
  41: /**
  42:  * Bidirectional Algorithm implementation.
  43:  *
  44:  * TODO/FIXME Only one method <code>requiresBidi</code> is implemented
  45:  * for now by using <code>Character</code>. The full algorithm is <a
  46:  * href="http://www.unicode.org/unicode/reports/tr9/">Unicode Standard
  47:  * Annex #9: The Bidirectional Algorithm</a>. A full implementation is
  48:  * <a href="http://fribidi.org/">GNU FriBidi</a>.
  49:  */
  50: public class Bidi
  51: {
  52:   /**
  53:    * Returns false if all characters in the text between start and end
  54:    * are all left-to-right text. This implementation is just calls
  55:    * <code>Character.getDirectionality(char)</code> on all characters
  56:    * and makes sure all characters are either explicitly left-to-right
  57:    * or neutral in directionality (character types L, EN, ES, ET, AN,
  58:    * CS, S and WS).
  59:    */
  60:   public static boolean requiresBidi(char[] text, int start, int end)
  61:   {
  62:     for (int i = start; i < end; i++)
  63:       {
  64:     byte dir = Character.getDirectionality(text[i]);
  65:     if (dir != Character.DIRECTIONALITY_LEFT_TO_RIGHT
  66:         && dir != Character.DIRECTIONALITY_EUROPEAN_NUMBER
  67:         && dir != Character.DIRECTIONALITY_EUROPEAN_NUMBER_SEPARATOR
  68:         && dir != Character.DIRECTIONALITY_EUROPEAN_NUMBER_TERMINATOR
  69:         && dir != Character.DIRECTIONALITY_ARABIC_NUMBER
  70:         && dir != Character.DIRECTIONALITY_COMMON_NUMBER_SEPARATOR
  71:         && dir != Character.DIRECTIONALITY_SEGMENT_SEPARATOR
  72:         && dir != Character.DIRECTIONALITY_WHITESPACE)
  73:       return true;
  74:       }
  75: 
  76:     return false;
  77:   }
  78: }