case-study/jdt-before/ui/org/eclipse/jdt/internal/ui/text/JavaWordFinder.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2011 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/epl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package org.eclipse.jdt.internal.ui.text;
  12
  13
  14 import com.ibm.icu.text.UTF16;
  15
  16 import org.eclipse.jface.text.BadLocationException;
  17 import org.eclipse.jface.text.IDocument;
  18 import org.eclipse.jface.text.IRegion;
  19 import org.eclipse.jface.text.Region;
  20
  21 public class JavaWordFinder {
  22
  23         public static IRegion findWord(IDocument document, int offset) {
  24
  25                 int start= -2;
  26                 int end= -1;
  27
  28                 try {
  29                         int pos= offset;
  30                         char c;
  31
  32                         while (pos >= 0) {
  33                                 c= document.getChar(pos);
  34                                 if (!Character.isJavaIdentifierPart(c)) {
  35                                         // Check for surrogates
  36                                         if (UTF16.isSurrogate(c)) {
  37                                                 /*
  38                                                  * XXX: Here we should create the code point and test whether
  39                                                  * it is a Java identifier part. Currently this is not possible
  40                                                  * because java.lang.Character in 1.4 does not support surrogates
  41                                                  * and because com.ibm.icu.lang.UCharacter.isJavaIdentifierPart(int)
  42                                                  * is not correctly implemented.
  43                                                  */
  44                                         } else {
  45                                                 break;
  46                                         }
  47                                 }
  48                                 --pos;
  49                         }
  50                         start= pos;
  51
  52                         pos= offset;
  53                         int length= document.getLength();
  54
  55                         while (pos < length) {
  56                                 c= document.getChar(pos);
  57                                 if (!Character.isJavaIdentifierPart(c)) {
  58                                         if (UTF16.isSurrogate(c)) {
  59                                                 /*
  60                                                  * XXX: Here we should create the code point and test whether
  61                                                  * it is a Java identifier part. Currently this is not possible
  62                                                  * because java.lang.Character in 1.4 does not support surrogates
  63                                                  * and because com.ibm.icu.lang.UCharacter.isJavaIdentifierPart(int)
  64                                                  * is not correctly implemented.
  65                                                  */
  66                                         } else {
  67                                                 break;
  68                                         }
  69
  70                                 }
  71                                 ++pos;
  72                         }
  73                         end= pos;
  74
  75                 } catch (BadLocationException x) {
  76                 }
  77
  78                 if (start >= -1 && end > -1) {
  79                         if (start == offset && end == offset)
  80                                 return new Region(offset, 0);
  81                         else if (start == offset)
  82                                 return new Region(start, end - start);
  83                         else
  84                                 return new Region(start + 1, end - start - 1);
  85                 }
  86
  87                 return null;
  88         }
  89 }