Source for javax.swing.text.PlainDocument

   1: /* PlainDocument.java --
   2:    Copyright (C) 2002, 2004  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 javax.swing.text;
  40: 
  41: import java.util.ArrayList;
  42: 
  43: public class PlainDocument extends AbstractDocument
  44: {
  45:   private static final long serialVersionUID = 4758290289196893664L;
  46:     
  47:   public static final String lineLimitAttribute = "lineLimit";
  48:   public static final String tabSizeAttribute = "tabSize";
  49: 
  50:   private BranchElement rootElement;
  51:   private int tabSize;
  52:   
  53:   public PlainDocument()
  54:   {
  55:     this(new GapContent());
  56:   }
  57: 
  58:   public PlainDocument(AbstractDocument.Content content)
  59:   {
  60:     super(content);
  61:     tabSize = 8;
  62:     rootElement = (BranchElement) createDefaultRoot();
  63:   }
  64: 
  65:   private void reindex()
  66:   {
  67:     Element[] lines;
  68:     try 
  69:       {
  70:         String str = content.getString(0, content.length());
  71: 
  72:         ArrayList elts = new ArrayList();
  73:         int j = 0;
  74:         for (int i = str.indexOf('\n', 0); i != -1; i = str.indexOf('\n', i + 1))
  75:           {
  76:             elts.add(createLeafElement(rootElement, SimpleAttributeSet.EMPTY, j, i + 1));
  77:             j = i + 1;
  78:           }
  79:         
  80:         if (j < content.length())
  81:           elts.add(createLeafElement(rootElement, SimpleAttributeSet.EMPTY, j, content.length()));
  82:         
  83:         lines = new Element[elts.size()];
  84:         for (int i = 0; i < elts.size(); ++i)
  85:           lines[i] = (Element) elts.get(i);
  86:       }
  87:     catch (BadLocationException e)
  88:       {
  89:         lines = new Element[1];
  90:         lines[0] = createLeafElement(rootElement, SimpleAttributeSet.EMPTY, 0, 1);
  91:       }
  92: 
  93:     ((BranchElement) rootElement).replace(0, rootElement.getElementCount(), lines);
  94:   }
  95: 
  96:   protected AbstractDocument.AbstractElement createDefaultRoot()
  97:   {
  98:     BranchElement root =
  99:       (BranchElement) createBranchElement(null, SimpleAttributeSet.EMPTY);
 100: 
 101:     Element[] array = new Element[1];
 102:     array[0] = createLeafElement(root, SimpleAttributeSet.EMPTY, 0, 1);
 103:     root.replace(0, 0, array);
 104:     
 105:     return root;
 106:   }
 107: 
 108:   protected void insertUpdate(DefaultDocumentEvent event, AttributeSet attributes)
 109:   {
 110:     reindex();
 111: 
 112:     super.insertUpdate(event, attributes);
 113:   }
 114: 
 115:   protected void removeUpdate(DefaultDocumentEvent event)
 116:   {
 117:     super.removeUpdate(event);
 118: 
 119:     int p0 = event.getOffset();
 120:     int len = event.getLength();
 121:     int p1 = len + p0;
 122: 
 123:     // check if we must collapse some elements
 124:     int i1 = rootElement.getElementIndex(p0);
 125:     int i2 = rootElement.getElementIndex(p1);
 126:     if (i1 != i2)
 127:       {
 128:         Element el1 = rootElement.getElement(i1);
 129:         Element el2 = rootElement.getElement(i2);
 130:         int start = el1.getStartOffset();
 131:         int end = el2.getEndOffset();
 132:         // collapse elements if the removal spans more than 1 line
 133:         Element newEl = createLeafElement(rootElement,
 134:                                           SimpleAttributeSet.EMPTY,
 135:                                           start, end - len);
 136:         rootElement.replace(i1, i2 - i1, new Element[]{ newEl });
 137:       }
 138:   }
 139: 
 140:   public Element getDefaultRootElement()
 141:   {
 142:     return rootElement;
 143:   }
 144: 
 145:   public Element getParagraphElement(int pos)
 146:   {
 147:     Element root = getDefaultRootElement();
 148:     return root.getElement(root.getElementIndex(pos));
 149:   }
 150: }