net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpdt/internal/ui/text/java/JavaParameterListValidator.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2005 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 net.sourceforge.phpdt.internal.ui.text.java;
  12
  13 //incastrix
  14 //import org.eclipse.jface.text.Assert;
  15 import org.eclipse.core.runtime.Assert;
  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.ITextViewer;
  20 import org.eclipse.jface.text.TextPresentation;
  21 import org.eclipse.jface.text.contentassist.IContextInformation;
  22 import org.eclipse.jface.text.contentassist.IContextInformationPresenter;
  23 import org.eclipse.jface.text.contentassist.IContextInformationValidator;
  24 import org.eclipse.swt.SWT;
  25 import org.eclipse.swt.custom.StyleRange;
  26
  27 public class JavaParameterListValidator implements
  28                 IContextInformationValidator, IContextInformationPresenter {
  29
  30         private int fPosition;
  31
  32         private ITextViewer fViewer;
  33
  34         private IContextInformation fInformation;
  35
  36         private int fCurrentParameter;
  37
  38         public JavaParameterListValidator() {
  39         }
  40
  41         /**
  42          * @see IContextInformationValidator#install(IContextInformation,
  43          *      ITextViewer, int)
  44          * @see IContextInformationPresenter#install(IContextInformation,
  45          *      ITextViewer, int)
  46          */
  47         public void install(IContextInformation info, ITextViewer viewer,
  48                         int documentPosition) {
  49                 fPosition = documentPosition;
  50                 fViewer = viewer;
  51                 fInformation = info;
  52
  53                 fCurrentParameter = -1;
  54         }
  55
  56         private int getCommentEnd(IDocument d, int pos, int end)
  57                         throws BadLocationException {
  58                 while (pos < end) {
  59                         char curr = d.getChar(pos);
  60                         pos++;
  61                         if (curr == '*') {
  62                                 if (pos < end && d.getChar(pos) == '/') {
  63                                         return pos + 1;
  64                                 }
  65                         }
  66                 }
  67                 return end;
  68         }
  69
  70         private int getStringEnd(IDocument d, int pos, int end, char ch)
  71                         throws BadLocationException {
  72                 while (pos < end) {
  73                         char curr = d.getChar(pos);
  74                         pos++;
  75                         if (curr == '\\') {
  76                                 // ignore escaped characters
  77                                 pos++;
  78                         } else if (curr == ch) {
  79                                 return pos;
  80                         }
  81                 }
  82                 return end;
  83         }
  84
  85         private int getCharCount(IDocument document, int start, int end,
  86                         String increments, String decrements, boolean considerNesting)
  87                         throws BadLocationException {
  88
  89                 Assert.isTrue((increments.length() != 0 || decrements.length() != 0)
  90                                 && !increments.equals(decrements));
  91
  92                 int nestingLevel = 0;
  93                 int charCount = 0;
  94                 while (start < end) {
  95                         char curr = document.getChar(start++);
  96                         switch (curr) {
  97                         case '/':
  98                                 if (start < end) {
  99                                         char next = document.getChar(start);
 100                                         if (next == '*') {
 101                                                 // a comment starts, advance to the comment end
 102                                                 start = getCommentEnd(document, start + 1, end);
 103                                         } else if (next == '/') {
 104                                                 // '//'-comment: nothing to do anymore on this line
 105                                                 start = end;
 106                                         }
 107                                 }
 108                                 break;
 109                         case '*':
 110                                 if (start < end) {
 111                                         char next = document.getChar(start);
 112                                         if (next == '/') {
 113                                                 // we have been in a comment: forget what we read before
 114                                                 charCount = 0;
 115                                                 ++start;
 116                                         }
 117                                 }
 118                                 break;
 119                         case '"':
 120                         case '\'':
 121                                 start = getStringEnd(document, start, end, curr);
 122                                 break;
 123                         default:
 124
 125                                 if (considerNesting) {
 126
 127                                         if ('(' == curr)
 128                                                 ++nestingLevel;
 129                                         else if (')' == curr)
 130                                                 --nestingLevel;
 131
 132                                         if (nestingLevel != 0)
 133                                                 break;
 134                                 }
 135
 136                                 if (increments.indexOf(curr) >= 0) {
 137                                         ++charCount;
 138                                 }
 139
 140                                 if (decrements.indexOf(curr) >= 0) {
 141                                         --charCount;
 142                                 }
 143                         }
 144                 }
 145
 146                 return charCount;
 147         }
 148
 149         /**
 150          * @see IContextInformationValidator#isContextInformationValid(int)
 151          */
 152         public boolean isContextInformationValid(int position) {
 153
 154                 try {
 155                         if (position < fPosition)
 156                                 return false;
 157
 158                         IDocument document = fViewer.getDocument();
 159                         IRegion line = document.getLineInformationOfOffset(fPosition);
 160
 161                         if (position < line.getOffset() || position >= document.getLength())
 162                                 return false;
 163
 164                         return getCharCount(document, fPosition, position,
 165                                         "(<", ")>", false) >= 0; //$NON-NLS-1$//$NON-NLS-2$
 166
 167                 } catch (BadLocationException x) {
 168                         return false;
 169                 }
 170         }
 171
 172         /**
 173          * @see IContextInformationPresenter#updatePresentation(int,
 174          *      TextPresentation)
 175          */
 176         public boolean updatePresentation(int position,
 177                         TextPresentation presentation) {
 178
 179                 int currentParameter = -1;
 180
 181                 try {
 182                         currentParameter = getCharCount(fViewer.getDocument(), fPosition,
 183                                         position, ",", "", true); //$NON-NLS-1$//$NON-NLS-2$
 184                 } catch (BadLocationException x) {
 185                         return false;
 186                 }
 187
 188                 if (fCurrentParameter != -1) {
 189                         if (currentParameter == fCurrentParameter)
 190                                 return false;
 191                 }
 192
 193                 presentation.clear();
 194                 fCurrentParameter = currentParameter;
 195
 196                 String s = fInformation.getInformationDisplayString();
 197                 int start = 0;
 198                 int occurrences = 0;
 199                 while (occurrences < fCurrentParameter) {
 200                         int found = s.indexOf(',', start);
 201                         if (found == -1)
 202                                 break;
 203                         start = found + 1;
 204                         ++occurrences;
 205                 }
 206
 207                 if (occurrences < fCurrentParameter) {
 208                         presentation.addStyleRange(new StyleRange(0, s.length(), null,
 209                                         null, SWT.NORMAL));
 210                         return true;
 211                 }
 212
 213                 if (start == -1)
 214                         start = 0;
 215
 216                 int end = s.indexOf(',', start);
 217                 if (end == -1)
 218                         end = s.length();
 219
 220                 if (start > 0)
 221                         presentation.addStyleRange(new StyleRange(0, start, null, null,
 222                                         SWT.NORMAL));
 223
 224                 if (end > start)
 225                         presentation.addStyleRange(new StyleRange(start, end - start, null,
 226                                         null, SWT.BOLD));
 227
 228                 if (end < s.length())
 229                         presentation.addStyleRange(new StyleRange(end, s.length() - end,
 230                                         null, null, SWT.NORMAL));
 231
 232                 return true;
 233         }
 234 }