Source for java.awt.font.LineBreakMeasurer

   1: /* LineBreakMeasurer.java
   2:    Copyright (C) 2006 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.awt.font;
  40: 
  41: import java.text.AttributedCharacterIterator;
  42: import java.text.AttributedString;
  43: import java.text.BreakIterator;
  44: import java.awt.Shape;
  45: 
  46: public final class LineBreakMeasurer
  47: {
  48:   private AttributedCharacterIterator text;
  49:   private int position;
  50:   private TextMeasurer tm; 
  51:   private int numChars;
  52: 
  53:   public LineBreakMeasurer(AttributedCharacterIterator text, 
  54:                BreakIterator breakIter, FontRenderContext frc)
  55:   {
  56:     this( text, frc );
  57:   }
  58: 
  59:   public LineBreakMeasurer(AttributedCharacterIterator text, 
  60:                FontRenderContext frc)
  61:   {
  62:     this.text = text;
  63:     position = 0;
  64:     numChars = text.getEndIndex();
  65:     tm = new TextMeasurer( text, frc );
  66:   }
  67: 
  68:   public void deleteChar(AttributedCharacterIterator newParagraph, 
  69:              int deletePos)
  70:   {
  71:     tm.deleteChar( newParagraph, deletePos );
  72:     position = 0;
  73:   }
  74: 
  75:   public void insertChar(AttributedCharacterIterator newParagraph, 
  76:              int insertPos)
  77:   {
  78:     tm.insertChar( newParagraph, insertPos );
  79:     position = 0;
  80:   }
  81: 
  82:   public TextLayout nextLayout(float wrappingWidth)
  83:   {
  84:     return nextLayout( wrappingWidth, numChars, false );
  85:   }
  86: 
  87:   public TextLayout nextLayout(float wrappingWidth, int offsetLimit, 
  88:                    boolean requireNextWord)
  89:   {
  90:     int next = nextOffset( wrappingWidth, offsetLimit, requireNextWord );
  91:     TextLayout tl = tm.getLayout( position, next );
  92:     position = next;
  93:     return tl;
  94:   }
  95: 
  96:   public int nextOffset(float wrappingWidth)
  97:   {
  98:     return nextOffset( wrappingWidth, numChars, false );
  99:   }
 100: 
 101:   public int nextOffset(float wrappingWidth, int offsetLimit, 
 102:             boolean requireNextWord)
 103:   {
 104:     int guessOffset = tm.getLineBreakIndex(position, wrappingWidth);
 105:     if( offsetLimit > numChars )
 106:       offsetLimit = numChars;
 107: 
 108:     if( guessOffset > offsetLimit )
 109:       {
 110:     text.setIndex( offsetLimit );
 111:     return offsetLimit;
 112:       }
 113: 
 114:     text.setIndex( guessOffset );
 115: 
 116:     // If we're on a breaking character, return directly
 117:     if( Character.isWhitespace( text.current() ) )
 118:       return guessOffset;
 119: 
 120:     // Otherwise jump forward or backward to the last such char.
 121:     if( !requireNextWord )
 122:       while( !Character.isWhitespace( text.previous() ) && 
 123:          guessOffset > position )
 124:     guessOffset--; 
 125:     else
 126:       while( !Character.isWhitespace( text.next() ) && 
 127:          guessOffset < offsetLimit )
 128:     guessOffset++;
 129:     
 130:     if( guessOffset > offsetLimit )
 131:       {
 132:     text.setIndex( offsetLimit );
 133:     return offsetLimit;
 134:       }
 135: 
 136:     text.setIndex( guessOffset );
 137: 
 138:     return guessOffset;
 139:   }
 140: 
 141:   public void setPosition(int newPosition)
 142:   {
 143:     position = newPosition;
 144:   }
 145: 
 146:   public int getPosition()
 147:   {
 148:     return position;
 149:   }
 150: }