| /******************************************************************************* |
| * Copyright (c) 2000, 2011 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| * Christian Plesner Hansen (plesner@quenta.org) - changed implementation to use DefaultCharacterPairMatcher |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.ui.text; |
| |
| import org.eclipse.jface.text.BadLocationException; |
| import org.eclipse.jface.text.IDocument; |
| import org.eclipse.jface.text.IRegion; |
| import org.eclipse.jface.text.TextUtilities; |
| import org.eclipse.jface.text.source.DefaultCharacterPairMatcher; |
| |
| import org.eclipse.jdt.core.JavaCore; |
| |
| import org.eclipse.jdt.ui.text.IJavaPartitions; |
| |
| /** |
| * Helper class for match pairs of characters. |
| */ |
| public final class JavaPairMatcher extends DefaultCharacterPairMatcher implements ISourceVersionDependent { |
| |
| /** |
| * Stores the source version state. |
| * @since 3.1 |
| */ |
| private boolean fHighlightAngularBrackets= false; |
| |
| |
| public JavaPairMatcher(char[] pairs) { |
| super(pairs, IJavaPartitions.JAVA_PARTITIONING); |
| } |
| |
| /* @see ICharacterPairMatcher#match(IDocument, int) */ |
| @Override |
| public IRegion match(IDocument document, int offset) { |
| try { |
| return performMatch(document, offset); |
| } catch (BadLocationException ble) { |
| return null; |
| } |
| } |
| |
| /* |
| * Performs the actual work of matching for #match(IDocument, int). |
| */ |
| private IRegion performMatch(IDocument document, int offset) throws BadLocationException { |
| if (offset < 0 || document == null) return null; |
| final char prevChar= document.getChar(Math.max(offset - 1, 0)); |
| if ((prevChar == '<' || prevChar == '>') && !fHighlightAngularBrackets) |
| return null; |
| if (prevChar == '<' && isLessThanOperator(document, offset - 1)) |
| return null; |
| final IRegion region= super.match(document, offset); |
| if (region == null) return region; |
| if (prevChar == '>') { |
| final int peer= region.getOffset(); |
| if (isLessThanOperator(document, peer)) return null; |
| } |
| return region; |
| } |
| |
| /** |
| * Returns true if the character at the specified offset is a |
| * less-than sign, rather than an type parameter list open |
| * angle bracket. |
| * |
| * @param document a document |
| * @param offset an offset within the document |
| * @return true if the character at the specified offset is not |
| * a type parameter start bracket |
| * @throws BadLocationException |
| */ |
| private boolean isLessThanOperator(IDocument document, int offset) throws BadLocationException { |
| if (offset < 0) return false; |
| JavaHeuristicScanner scanner= new JavaHeuristicScanner(document, IJavaPartitions.JAVA_PARTITIONING, TextUtilities.getContentType(document, IJavaPartitions.JAVA_PARTITIONING, offset, false)); |
| return !isTypeParameterBracket(offset, document, scanner); |
| } |
| |
| /** |
| * Checks if the angular bracket at <code>offset</code> is a type |
| * parameter bracket. |
| * |
| * @param offset the offset of the opening bracket |
| * @param document the document |
| * @param scanner a java heuristic scanner on <code>document</code> |
| * @return <code>true</code> if the bracket is part of a type parameter, |
| * <code>false</code> otherwise |
| * @since 3.1 |
| */ |
| private boolean isTypeParameterBracket(int offset, IDocument document, JavaHeuristicScanner scanner) { |
| /* |
| * type parameter come after braces (closing or opening), semicolons, or after |
| * a Type name (heuristic: starts with capital character, or after a modifier |
| * keyword in a method declaration (visibility, static, synchronized, final) |
| */ |
| |
| try { |
| IRegion line= document.getLineInformationOfOffset(offset); |
| |
| int prevToken= scanner.previousToken(offset - 1, line.getOffset()); |
| int prevTokenOffset= scanner.getPosition() + 1; |
| String previous= prevToken == Symbols.TokenEOF ? null : document.get(prevTokenOffset, offset - prevTokenOffset).trim(); |
| |
| if ( prevToken == Symbols.TokenLBRACE |
| || prevToken == Symbols.TokenRBRACE |
| || prevToken == Symbols.TokenSEMICOLON |
| || prevToken == Symbols.TokenSYNCHRONIZED |
| || prevToken == Symbols.TokenSTATIC |
| || (prevToken == Symbols.TokenIDENT && isTypeParameterIntroducer(previous)) |
| || prevToken == Symbols.TokenEOF) |
| return true; |
| } catch (BadLocationException e) { |
| return false; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Returns <code>true</code> if <code>identifier</code> is an identifier |
| * that could come right before a type parameter list. It uses a heuristic: |
| * if the identifier starts with an upper case, it is assumed a type name. |
| * Also, if <code>identifier</code> is a method modifier, it is assumed |
| * that the angular bracket is part of the generic type parameter of a |
| * method. |
| * |
| * @param identifier the identifier to check |
| * @return <code>true</code> if the identifier could introduce a type |
| * parameter list |
| * @since 3.1 |
| */ |
| private boolean isTypeParameterIntroducer(String identifier) { |
| return identifier.length() > 0 |
| && (Character.isUpperCase(identifier.charAt(0)) |
| || identifier.startsWith("final") //$NON-NLS-1$ |
| || identifier.startsWith("public") //$NON-NLS-1$ |
| || identifier.startsWith("public") //$NON-NLS-1$ |
| || identifier.startsWith("protected") //$NON-NLS-1$ |
| || identifier.startsWith("private")); //$NON-NLS-1$ |
| } |
| |
| /* |
| * @see org.eclipse.jdt.internal.ui.text.ISourceVersionDependent#setSourceVersion(java.lang.String) |
| */ |
| public void setSourceVersion(String version) { |
| if (JavaCore.VERSION_1_5.compareTo(version) <= 0) |
| fHighlightAngularBrackets= true; |
| else |
| fHighlightAngularBrackets= false; |
| } |
| } |