1) Fixed issue #852: Correct matching of closing brace with the according opening...
[phpeclipse.git] / net.sourceforge.phpeclipse / src / net / sourceforge / phpdt / internal / ui / text / PHPPairMatcher.java
index 97a0edd..b43ff4e 100644 (file)
@@ -11,162 +11,223 @@ import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.Region;
+import org.eclipse.jface.text.source.ICharacterPairMatcher;
 
 /**
  * Helper class for match pairs of characters.
  */
-public class PHPPairMatcher {
-       
-       
-       public static final int LEFT=      1;
-       public static final int RIGHT= 2;
-
-       
-       protected char[] fPairs;
+public class PHPPairMatcher implements ICharacterPairMatcher {
+       protected char[]    fPairs;           // Holds the brace pairs
+
        protected IDocument fDocument;
-       protected int fOffset;
-       
-       protected int fStartPos;
-       protected int fEndPos;
+
+       protected int       fOffset;          // The current text position from which we search
+       protected int       nPosOpening;      // The position of the opening brace
+       protected int       nPosClosing;      // The position of the closing brace
        protected int fAnchor;
-       
-       protected PHPCodeReader fReader= new PHPCodeReader();
-       
-       
+
+       protected PHPCodeReader fReader = new PHPCodeReader();
+
+       /**
+        *
+        * @param pairs The array of opening and closing braces we need for searching the brace matching
+        */
+
        public PHPPairMatcher(char[] pairs) {
-               fPairs= pairs;
+               fPairs = pairs;
+       }
+
+       /*
+        * @see org.eclipse.jface.text.source.ICharacterPairMatcher#clear()
+        */
+       public void clear() {
+               if (fReader != null) {
+                       try {
+                               fReader.close();
+                       } catch (IOException x) {
+                               // ignore
+                       }
+               }
        }
-       
-       public IRegion match(IDocument document, int offset) {
 
-               fOffset= offset;
+       /**
+        * Try to find a matching pair of opening and closing braces
+        *
+        * @return  Returns a region if a matching pair was found.
+        */
+       public IRegion match(IDocument document, int offset) {
+               fOffset = offset;
 
-               if (fOffset < 0)
+               if (fOffset < 0) {
                        return null;
+               }
+
+               fDocument = document;
 
-               fDocument= document;
+               if (matchPairsAt ()) {                                                                          // If we found a pair of opening and closing braces
+                       return new Region (nPosOpening, nPosClosing - nPosOpening + 1);
+               }
 
-               if (matchPairsAt() && fStartPos != fEndPos)
-                       return new Region(fStartPos, fEndPos - fStartPos + 1);
-                       
                return null;
        }
-       
+
        public int getAnchor() {
                return fAnchor;
        }
-       
+
        public void dispose() {
-               fDocument= null;
+               fDocument = null;
                if (fReader != null) {
                        try {
                                fReader.close();
                        } catch (IOException x) {
                                // ignore
                        }
-                       fReader= null;
+                       fReader = null;
                }
        }
-       
-       protected boolean matchPairsAt() {
 
+       /**
+        * Take the character from the current text position, checks for opening or closing braces and search for
+        * the corresponding opening or closing brace
+        *
+        * @return True if a pair was found
+        */
+       protected boolean matchPairsAt() {
                int i;
-               int pairIndex1= fPairs.length;
-               int pairIndex2= fPairs.length;
+               int   nIndexOpen  = fPairs.length;        // Opening index
+               int   nIndexClose = fPairs.length;
+               char  cCurrentChar;                       // The character from the current text position
+               char  cPrevChar;                          // The character from the previouis text position, just
+                                                         // for the case the user pointed the cursor after the opening or closing brace
 
-               fStartPos= -1;
-               fEndPos= -1;
+               nPosOpening = -1;
+               nPosClosing = -1;
 
                // get the chars preceding and following the start position
                try {
-
-                       char prevChar= fDocument.getChar(Math.max(fOffset - 1, 0));
-                       char nextChar= fDocument.getChar(fOffset);
+            cCurrentChar = fDocument.getChar (fOffset);
+                       cPrevChar    = fDocument.getChar (Math.max (fOffset - 1, 0));
 
                        // search for opening peer character next to the activation point
-                       for (i= 0; i < fPairs.length; i= i + 2) {
-                               if (nextChar == fPairs[i]) {
-                                       fStartPos= fOffset;
-                                       pairIndex1= i;
-                               } else if (prevChar == fPairs[i]) {
-                                       fStartPos= fOffset - 1;
-                                       pairIndex1= i;
+                       for (i = 0; i < fPairs.length; i = i + 2) {     // The opening brace is on even indexes
+                               if (cCurrentChar == fPairs[i]) {            // If the current character matches an opening brace
+                                       nPosOpening  = fOffset;                 // Remember the character position
+                                       nIndexOpen   = i;                       // and remember the opening brace for which we search the closing one
+                               }
+                               else if (cPrevChar == fPairs[i]) {          // If the current character is not an opening, but the previous character is an opening brace
+                                       nPosOpening  = fOffset - 1;             // Remember the character position
+                                       nIndexOpen   = i;                       // and remember the opening brace for which we search the closing one
                                }
                        }
-                       
+
                        // search for closing peer character next to the activation point
-                       for (i= 1; i < fPairs.length; i= i + 2) {
-                               if (prevChar == fPairs[i]) {
-                                       fEndPos= fOffset - 1;
-                                       pairIndex2= i;
-                               } else if (nextChar == fPairs[i]) {
-                                       fEndPos= fOffset;
-                                       pairIndex2= i;
+
+                       if (nPosOpening < 0) {                              // If we didn't find an opening brace
+                               for (i = 1; i < fPairs.length; i = i + 2) {     // The closing brace is on odd indexes
+                                       if (cCurrentChar == fPairs[i]) {            // If the current character matches an closing brace
+                                               nPosClosing  = fOffset;                 // Remember the character position
+                                               nIndexClose  = i;                       // and remember the opening brace for which we search the closing one
+                                       }
+                                       else if (cPrevChar == fPairs[i]) {          // If the current character is not an opening, but the previous character is an opening brace
+                                               nPosClosing  = fOffset - 1;             // Remember the character position
+                                               nIndexClose  = i;                       // and remember the opening brace for which we search the closing one
+                                       }
                                }
                        }
 
-                       if (fEndPos > -1) {
-                               fAnchor= RIGHT;
-                               fStartPos= searchForOpeningPeer(fEndPos, fPairs[pairIndex2 - 1], fPairs[pairIndex2], fDocument);
-                               if (fStartPos > -1)
-                                       return true;
-                               else
-                                       fEndPos= -1;
-                       }       else if (fStartPos > -1) {
-                               fAnchor= LEFT;
-                               fEndPos= searchForClosingPeer(fStartPos, fPairs[pairIndex1], fPairs[pairIndex1 + 1], fDocument);
-                               if (fEndPos > -1)
-                                       return true;
-                               else
-                                       fStartPos= -1;
+                       if (nPosClosing > -1) {                             // If we found a closing brace on current position (or before)
+                               fAnchor = RIGHT;
+                               nPosOpening = searchForOpeningPeer (nPosClosing, fPairs[nIndexClose - 1], fPairs[nIndexClose], fDocument);
+
+                               return (nPosOpening > -1);                      // If we found a opening brace, return true
                        }
+                       else if (nPosOpening > -1) {                        // If we found a opening brace on current position (or before)
+                               fAnchor = LEFT;
+                               nPosClosing = searchForClosingPeer (nPosOpening, fPairs[nIndexOpen], fPairs[nIndexOpen + 1], fDocument);
 
-               } catch (BadLocationException x) {
-               } catch (IOException x) {
+                               return (nPosClosing > -1);                      // If we found an closing brace for this opening brace return true
+                       }
+                       }
+               catch (BadLocationException x) {
+               }
+               catch (IOException x) {
                }
 
                return false;
        }
-       
-       protected int searchForClosingPeer(int offset, int openingPeer, int closingPeer, IDocument document) throws IOException {
-               
-               fReader.configureForwardReader(document, offset + 1, document.getLength(), true, true);
-               
-               int stack= 1;
-               int c= fReader.read();
-               while (c != PHPCodeReader.EOF) {
-                       if (c == openingPeer && c != closingPeer)
-                               stack++;
-                       else if (c == closingPeer)
-                               stack--;
-                               
-                       if (stack == 0)
-                               return fReader.getOffset();
-                               
-                       c= fReader.read();
+
+       /**
+        *
+        * @param offset               The search start position
+        * @param openingPeer          The opening brace we had found
+        * @param closingPeer          The closing brace we search for
+        * @param document             The document we currently are in
+        *
+        * @return
+        *
+        * @throws IOException
+        */
+       protected int searchForClosingPeer (int offset, char openingPeer,
+                                                   char closingPeer, IDocument document) throws IOException {
+               fReader.configureForwardReader (document, offset + 1, document.getLength(), true, true);
+
+               int stack = 1;                                  // As we have already the opening brace
+               int c     = fReader.read ();                            // Read character on position one after the opening brace
+
+               while (c != PHPCodeReader.EOF) {                // As long as we are not at the end
+                       if ((c == openingPeer) &&                   // If character is opening brace again
+                           (c != closingPeer)) {                   // and not a closing brace (how could it be?)
+                               stack++;                                // put it on stack
+                       }
+                       else if (c == closingPeer) {                // If it's a closing brace
+                               stack--;                                // Decrement level counter
+                       }
+
+                       if (stack == 0) {                           // If we found the matching closing brace
+                               return fReader.getOffset ();            // return the position of this closing brace
+                       }
+
+                       c = fReader.read ();                        // Read the next character
                }
-               
-               return  -1;
+
+               return -1;
        }
-       
-       protected int searchForOpeningPeer(int offset, int openingPeer, int closingPeer, IDocument document) throws IOException {
-               
+
+       /**
+        *
+        * @param offset               The search start position
+        * @param openingPeer          The opening brace we search for
+        * @param closingPeer          The closing brace we search for
+        * @param document             The document we currently are in
+        *
+        * @return
+        *
+        * @throws IOException
+        */
+       protected int searchForOpeningPeer (int offset, char openingPeer,
+                                               char closingPeer, IDocument document) throws IOException {
                fReader.configureBackwardReader(document, offset, true, true);
-               
-               int stack= 1;
-               int c= fReader.read();
-               while (c != PHPCodeReader.EOF) {
-                       if (c == closingPeer && c != openingPeer)
-                               stack++;
-                       else if (c == openingPeer)
-                               stack--;
-                               
-                       if (stack == 0)
-                               return fReader.getOffset();
-                               
-                       c= fReader.read();
+
+               int stack = 1;                                  // As we have already the opening brace
+               int c     = fReader.read ();                    // Read character on position one before the closing brace
+
+               while (c != PHPCodeReader.EOF) {                // As long as we are not at the start of text
+                       if ((c == closingPeer) &&                   // If character is closing brace again
+                           (c != openingPeer)) {                   // and not a opening brace (how could it be?)
+                               stack++;                                // put it on stack
+                       }
+                       else if (c == openingPeer) {                // If it's a opening brace
+                               stack--;                                // Decrement level counter
+                       }
+
+                       if (stack == 0) {                           // If we found the matching closing brace
+                               return fReader.getOffset ();            // return the position of this closing brace
+                       }
+
+                       c = fReader.read ();                        // Read the previous character
                }
-               
+
                return -1;
        }
-}
+}
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