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,
 109:                               AttributeSet attributes)
 110:   {
 111:     int offset = event.getOffset();
 112:     int end = offset + event.getLength();
 113:     int elementIndex = rootElement.getElementIndex(offset);
 114:     Element firstElement = rootElement.getElement(elementIndex);
 115:     
 116:     // If we're inserting immediately after a newline we have to fix the 
 117:     // Element structure.
 118:     if (offset > 0)
 119:       {
 120:         try
 121:         {
 122:           String s = getText(offset - 1, 1);
 123:           if (s.equals("\n"))
 124:             {
 125:               int newEl2EndOffset = end;
 126:               boolean replaceNext = false;
 127:               if (rootElement.getElementCount() > elementIndex + 1)
 128:                 {
 129:                   replaceNext = true;
 130:                   newEl2EndOffset = 
 131:                     rootElement.getElement(elementIndex + 1).getEndOffset();
 132:                 }
 133:               Element newEl1 = 
 134:                 createLeafElement(rootElement, firstElement.getAttributes(), 
 135:                                   firstElement.getStartOffset(), offset);
 136:               Element newEl2 = 
 137:                 createLeafElement (rootElement, firstElement.getAttributes(), 
 138:                                    offset, newEl2EndOffset);
 139:               if (replaceNext)
 140:                 rootElement.replace(elementIndex, 2, new Element[] { newEl1, newEl2 });
 141:               else
 142:                 rootElement.replace(elementIndex, 1, new Element[] { newEl1, newEl2 });
 143:               firstElement = newEl2;
 144:               elementIndex ++;
 145:             }
 146:         }
 147:         catch (BadLocationException ble)
 148:         {          
 149:           // This shouldn't happen.
 150:           AssertionError ae = new AssertionError();
 151:           ae.initCause(ble);
 152:           throw ae;
 153:         }        
 154:       }
 155: 
 156:     // added and removed are Element arrays used to add an ElementEdit
 157:     // to the DocumentEvent if there were entire lines added or removed.
 158:     Element[] removed = new Element[1];
 159:     Element[] added;
 160:     try 
 161:       {
 162:         String str = content.getString(0, content.length());
 163:         ArrayList elts = new ArrayList();
 164: 
 165:         // Determine how many NEW lines were added by finding the newline
 166:         // characters within the newly inserted text
 167:         int j = firstElement.getStartOffset();
 168:         int i = str.indexOf('\n', offset);
 169:         while (i != -1 && i <= end)
 170:           {            
 171:             // For each new line, create a new element
 172:             elts.add(createLeafElement(rootElement, SimpleAttributeSet.EMPTY,
 173:                                        j, i + 1));
 174:             j = i + 1;
 175:             if (j >= str.length())
 176:               break;
 177:             i = str.indexOf('\n', j);
 178:           }
 179:         // If there were new lines added we have to add an ElementEdit to 
 180:         // the DocumentEvent and we have to call rootElement.replace to 
 181:         // insert the new lines
 182:         if (elts.size() != 0)
 183:           {
 184:             // Set up the ElementEdit by filling the added and removed 
 185:             // arrays with the proper Elements
 186:             added = new Element[elts.size()];
 187:             for (int k = 0; k < elts.size(); ++k)
 188:               added[k] = (Element) elts.get(k);
 189:             removed[0] = firstElement;
 190:             
 191:             // Now create and add the ElementEdit
 192:             ElementEdit e = new ElementEdit(rootElement, elementIndex, removed,
 193:                                             added);
 194:             event.addEdit(e);
 195:             
 196:             // And call replace to actually make the changes
 197:             ((BranchElement) rootElement).replace(elementIndex, 1, added);
 198:           }
 199:       }
 200:     catch (BadLocationException e)
 201:       {
 202:         // This shouldn't happen so we throw an AssertionError
 203:         AssertionError ae = new AssertionError();
 204:         ae.initCause(e);
 205:         throw ae;
 206:       }
 207:     super.insertUpdate(event, attributes);
 208:   }
 209: 
 210:   protected void removeUpdate(DefaultDocumentEvent event)
 211:   {
 212:     super.removeUpdate(event);
 213: 
 214:     // added and removed are Element arrays used to add an ElementEdit
 215:     // to the DocumentEvent if there were entire lines added or removed
 216:     // from the Document
 217:     Element[] added = new Element[1];
 218:     Element[] removed;
 219:     int p0 = event.getOffset();
 220: 
 221:     // check if we must collapse some elements
 222:     int i1 = rootElement.getElementIndex(p0);
 223:     int i2 = rootElement.getElementIndex(p0 + event.getLength());
 224:     if (i1 != i2)
 225:       {
 226:         // If there were lines removed then we have to add an ElementEdit
 227:         // to the DocumentEvent so we set it up now by filling the Element
 228:         // arrays "removed" and "added" appropriately
 229:         removed = new Element [i2 - i1 + 1];
 230:         for (int i = i1; i <= i2; i++)
 231:           removed[i-i1] = rootElement.getElement(i);
 232:         
 233:         int start = rootElement.getElement(i1).getStartOffset();
 234:         int end = rootElement.getElement(i2).getEndOffset();        
 235:         added[0] = createLeafElement(rootElement,
 236:                                           SimpleAttributeSet.EMPTY,
 237:                                           start, end);
 238: 
 239:         // Now create and add the ElementEdit
 240:         ElementEdit e = new ElementEdit(rootElement, i1, removed, added);
 241:         event.addEdit(e);
 242: 
 243:         // collapse elements if the removal spans more than 1 line
 244:         rootElement.replace(i1, i2 - i1 + 1, added);
 245:       }
 246:   }
 247: 
 248:   public Element getDefaultRootElement()
 249:   {
 250:     return rootElement;
 251:   }
 252: 
 253:   public Element getParagraphElement(int pos)
 254:   {
 255:     Element root = getDefaultRootElement();
 256:     return root.getElement(root.getElementIndex(pos));
 257:   }
 258: 
 259:   /**
 260:    * Inserts a string into the document. If the document property
 261:    * '<code>filterNewLines</code>' is set to <code>Boolean.TRUE</code>, then
 262:    * all newlines in the inserted string are replaced by space characters,
 263:    * otherwise the superclasses behaviour is executed.
 264:    *
 265:    * Inserting content causes a write lock to be acquired during this method
 266:    * call.
 267:    *
 268:    * @param offs the offset at which to insert the string
 269:    * @param str the string to be inserted
 270:    * @param atts the text attributes of the string to be inserted
 271:    *
 272:    * @throws BadLocationException
 273:    */
 274:   public void insertString(int offs, String str, AttributeSet atts)
 275:     throws BadLocationException
 276:   {
 277:     String string = str;
 278:     if (str != null && Boolean.TRUE.equals(getProperty("filterNewlines")))
 279:       string = str.replaceAll("\n", " ");
 280:     super.insertString(offs, string, atts);
 281:   }
 282: }