X-Git-Url: http://git.phpeclipse.com diff --git a/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/text/PHPPairMatcher.java b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/text/PHPPairMatcher.java new file mode 100644 index 0000000..c23d428 --- /dev/null +++ b/net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/text/PHPPairMatcher.java @@ -0,0 +1,234 @@ +package net.sourceforge.phpdt.internal.ui.text; + +/* + * (c) Copyright IBM Corp. 2000, 2001. + * All Rights Reserved. + */ + +import java.io.IOException; + +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 implements ICharacterPairMatcher { + protected char[] fPairs; // Holds the brace pairs + + protected IDocument fDocument; + + 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(); + + /** + * + * @param pairs The array of opening and closing braces we need for searching the brace matching + */ + + public PHPPairMatcher (char[] pairs) { + fPairs = pairs; + } + + /* + * @see org.eclipse.jface.text.source.ICharacterPairMatcher#clear() + */ + public void clear() { + if (fReader != null) { + try { + fReader.close(); + } catch (IOException x) { + // ignore + } + } + } + + /** + * 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) { + return null; + } + + fDocument = document; + + if (matchPairsAt ()) { // If we found a pair of opening and closing braces + return new Region (nPosOpening, nPosClosing - nPosOpening + 1); + } + + return null; + } + + public int getAnchor() { + return fAnchor; + } + + public void dispose() { + fDocument = null; + if (fReader != null) { + try { + fReader.close(); + } catch (IOException x) { + // ignore + } + fReader = null; + } + } + + /** + * 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 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 + + nPosOpening = -1; + nPosClosing = -1; + + // get the chars preceding and following the start position + try { + 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) { // 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 + + 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 (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); + + return (nPosClosing > -1); // If we found an closing brace for this opening brace return true + } + } + catch (BadLocationException x) { + } + catch (IOException x) { + } + + return false; + } + + /** + * + * @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; + } + + /** + * + * @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; // 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; + } +}