net.sourceforge.phpeclipse/src/net/sourceforge/phpeclipse/editors/NonRuleBasedDamagerRepairer.java

   1 package net.sourceforge.phpeclipse.editors;
   2
   3 import org.eclipse.jface.text.BadLocationException;
   4 import org.eclipse.jface.text.DocumentEvent;
   5 import org.eclipse.jface.text.IDocument;
   6 import org.eclipse.jface.text.IRegion;
   7 import org.eclipse.jface.text.ITypedRegion;
   8 import org.eclipse.jface.text.Region;
   9 import org.eclipse.jface.text.TextAttribute;
  10 import org.eclipse.jface.text.TextPresentation;
  11 import org.eclipse.jface.text.presentation.IPresentationDamager;
  12 import org.eclipse.jface.text.presentation.IPresentationRepairer;
  13 import org.eclipse.jface.util.Assert;
  14 import org.eclipse.swt.custom.StyleRange;
  15
  16 public class NonRuleBasedDamagerRepairer
  17         implements IPresentationDamager, IPresentationRepairer {
  18
  19         /** The document this object works on */
  20         protected IDocument fDocument;
  21         /** The default text attribute if non is returned as data by the current token */
  22         protected TextAttribute fDefaultTextAttribute;
  23
  24         /**
  25          * Constructor for NonRuleBasedDamagerRepairer.
  26          */
  27         public NonRuleBasedDamagerRepairer(TextAttribute defaultTextAttribute) {
  28                 Assert.isNotNull(defaultTextAttribute);
  29
  30                 fDefaultTextAttribute = defaultTextAttribute;
  31         }
  32
  33         /**
  34          * @see IPresentationRepairer#setDocument(IDocument)
  35          */
  36         public void setDocument(IDocument document) {
  37                 fDocument = document;
  38         }
  39
  40         /**
  41          * Returns the end offset of the line that contains the specified offset or
  42          * if the offset is inside a line delimiter, the end offset of the next line.
  43          *
  44          * @param offset the offset whose line end offset must be computed
  45          * @return the line end offset for the given offset
  46          * @exception BadLocationException if offset is invalid in the current document
  47          */
  48         protected int endOfLineOf(int offset) throws BadLocationException {
  49
  50                 IRegion info = fDocument.getLineInformationOfOffset(offset);
  51                 if (offset <= info.getOffset() + info.getLength())
  52                         return info.getOffset() + info.getLength();
  53
  54                 int line = fDocument.getLineOfOffset(offset);
  55                 try {
  56                         info = fDocument.getLineInformation(line + 1);
  57                         return info.getOffset() + info.getLength();
  58                 } catch (BadLocationException x) {
  59                         return fDocument.getLength();
  60                 }
  61         }
  62
  63         /**
  64          * @see IPresentationDamager#getDamageRegion(ITypedRegion, DocumentEvent, boolean)
  65          */
  66         public IRegion getDamageRegion(
  67                 ITypedRegion partition,
  68                 DocumentEvent event,
  69                 boolean documentPartitioningChanged) {
  70                 if (!documentPartitioningChanged) {
  71                         try {
  72
  73                                 IRegion info =
  74                                         fDocument.getLineInformationOfOffset(event.getOffset());
  75                                 int start = Math.max(partition.getOffset(), info.getOffset());
  76
  77                                 int end =
  78                                         event.getOffset()
  79                                                 + (event.getText() == null
  80                                                         ? event.getLength()
  81                                                         : event.getText().length());
  82
  83                                 if (info.getOffset() <= end
  84                                         && end <= info.getOffset() + info.getLength()) {
  85                                         // optimize the case of the same line
  86                                         end = info.getOffset() + info.getLength();
  87                                 } else
  88                                         end = endOfLineOf(end);
  89
  90                                 end =
  91                                         Math.min(
  92                                                 partition.getOffset() + partition.getLength(),
  93                                                 end);
  94                                 return new Region(start, end - start);
  95
  96                         } catch (BadLocationException x) {
  97                         }
  98                 }
  99
 100                 return partition;
 101         }
 102
 103         /**
 104          * @see IPresentationRepairer#createPresentation(TextPresentation, ITypedRegion)
 105          */
 106         public void createPresentation(
 107                 TextPresentation presentation,
 108                 ITypedRegion region) {
 109                 addRange(
 110                         presentation,
 111                         region.getOffset(),
 112                         region.getLength(),
 113                         fDefaultTextAttribute);
 114         }
 115
 116         /**
 117          * Adds style information to the given text presentation.
 118          *
 119          * @param presentation the text presentation to be extended
 120          * @param offset the offset of the range to be styled
 121          * @param length the length of the range to be styled
 122          * @param attr the attribute describing the style of the range to be styled
 123          */
 124         protected void addRange(
 125                 TextPresentation presentation,
 126                 int offset,
 127                 int length,
 128                 TextAttribute attr) {
 129                 if (attr != null)
 130                         presentation.addStyleRange(
 131                                 new StyleRange(
 132                                         offset,
 133                                         length,
 134                                         attr.getForeground(),
 135                                         attr.getBackground(),
 136                                         attr.getStyle()));
 137         }
 138 }