| /******************************************************************************* |
| * 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 |
| *******************************************************************************/ |
| |
| package org.eclipse.jface.text; |
| |
| import java.text.CharacterIterator; |
| import java.util.Locale; |
| |
| import com.ibm.icu.text.BreakIterator; |
| |
| |
| /** |
| * Standard implementation of |
| * {@link org.eclipse.jface.text.ITextDoubleClickStrategy}. |
| * <p> |
| * Selects words using <code>java.text.BreakIterator</code> for the default |
| * locale.</p> |
| * |
| * @see java.text.BreakIterator |
| */ |
| public class DefaultTextDoubleClickStrategy implements ITextDoubleClickStrategy { |
| |
| |
| /** |
| * Implements a character iterator that works directly on |
| * instances of <code>IDocument</code>. Used to collaborate with |
| * the break iterator. |
| * |
| * @see IDocument |
| * @since 2.0 |
| */ |
| static class DocumentCharacterIterator implements CharacterIterator { |
| |
| /** Document to iterate over. */ |
| private IDocument fDocument; |
| /** Start offset of iteration. */ |
| private int fOffset= -1; |
| /** End offset of iteration. */ |
| private int fEndOffset= -1; |
| /** Current offset of iteration. */ |
| private int fIndex= -1; |
| |
| /** Creates a new document iterator. */ |
| public DocumentCharacterIterator() { |
| } |
| |
| /** |
| * Configures this document iterator with the document section to be visited. |
| * |
| * @param document the document to be iterated |
| * @param iteratorRange the range in the document to be iterated |
| */ |
| public void setDocument(IDocument document, IRegion iteratorRange) { |
| fDocument= document; |
| fOffset= iteratorRange.getOffset(); |
| fEndOffset= fOffset + iteratorRange.getLength(); |
| } |
| |
| @Override |
| public char first() { |
| fIndex= fOffset; |
| return current(); |
| } |
| |
| @Override |
| public char last() { |
| fIndex= fOffset < fEndOffset ? fEndOffset -1 : fEndOffset; |
| return current(); |
| } |
| |
| @Override |
| public char current() { |
| if (fOffset <= fIndex && fIndex < fEndOffset) { |
| try { |
| return fDocument.getChar(fIndex); |
| } catch (BadLocationException x) { |
| } |
| } |
| return DONE; |
| } |
| |
| @Override |
| public char next() { |
| ++fIndex; |
| int end= getEndIndex(); |
| if (fIndex >= end) { |
| fIndex= end; |
| return DONE; |
| } |
| return current(); |
| } |
| |
| @Override |
| public char previous() { |
| if (fIndex == fOffset) |
| return DONE; |
| |
| if (fIndex > fOffset) |
| -- fIndex; |
| |
| return current(); |
| } |
| |
| @Override |
| public char setIndex(int index) { |
| fIndex= index; |
| return current(); |
| } |
| |
| @Override |
| public int getBeginIndex() { |
| return fOffset; |
| } |
| |
| @Override |
| public int getEndIndex() { |
| return fEndOffset; |
| } |
| |
| @Override |
| public int getIndex() { |
| return fIndex; |
| } |
| |
| @Override |
| public Object clone() { |
| DocumentCharacterIterator i= new DocumentCharacterIterator(); |
| i.fDocument= fDocument; |
| i.fIndex= fIndex; |
| i.fOffset= fOffset; |
| i.fEndOffset= fEndOffset; |
| return i; |
| } |
| } |
| |
| |
| /** |
| * The document character iterator used by this strategy. |
| * @since 2.0 |
| */ |
| private DocumentCharacterIterator fDocIter= new DocumentCharacterIterator(); |
| |
| /** |
| * The locale specific word break iterator. |
| * @since 3.7 |
| */ |
| private BreakIterator fWordBreakIterator; |
| |
| /** |
| * The POSIX word break iterator. |
| * <p> |
| * Used to workaround ICU bug not treating '.' as word boundary, see |
| * http://bugs.icu-project.org/trac/ticket/8371 for details. |
| * </p> |
| * |
| * @since 3.7 |
| */ |
| private BreakIterator fPOSIXWordBreakIterator; |
| |
| |
| /** |
| * Creates a new default text double click strategy. |
| */ |
| public DefaultTextDoubleClickStrategy() { |
| } |
| |
| @Override |
| public void doubleClicked(ITextViewer text) { |
| |
| int offset= text.getSelectedRange().x; |
| |
| if (offset < 0) |
| return; |
| |
| final IDocument document= text.getDocument(); |
| IRegion region= findExtendedDoubleClickSelection(document, offset); |
| if (region == null) |
| region= findWord(document, offset); |
| if (region != null) |
| text.setSelectedRange(region.getOffset(), region.getLength()); |
| |
| } |
| |
| /** |
| * Tries to find a suitable double click selection for the given offset. |
| * <p> |
| * <strong>Note:</strong> This method must return <code>null</code> if it simply selects the word at |
| * the given offset. |
| * </p> |
| * |
| * @param document the document |
| * @param offset the offset |
| * @return the selection or <code>null</code> if none to indicate simple word selection |
| * @since 3.5 |
| */ |
| protected IRegion findExtendedDoubleClickSelection(IDocument document, int offset) { |
| return null; |
| } |
| |
| /** |
| * Tries to find the word at the given offset. |
| * |
| * @param document the document |
| * @param offset the offset |
| * @return the word or <code>null</code> if none |
| * @since 3.5 |
| */ |
| protected IRegion findWord(IDocument document, int offset) { |
| return findWord(document, offset, getWordBreakIterator()); |
| } |
| |
| /** |
| * Returns the locale specific word break iterator. |
| * |
| * @return the locale specific word break iterator |
| * @since 3.7 |
| */ |
| private BreakIterator getWordBreakIterator() { |
| if (fWordBreakIterator == null) |
| fWordBreakIterator= BreakIterator.getWordInstance(); |
| return fWordBreakIterator; |
| } |
| |
| /** |
| * Returns the POSIX word break iterator. |
| * |
| * <p> |
| * Used to workaround ICU bug not treating '.' as word boundary, see |
| * http://bugs.icu-project.org/trac/ticket/8371 for details. |
| * </p> |
| * |
| * @return the POSIX word break iterator. |
| * @since 3.7 |
| */ |
| private BreakIterator getPOSIXWordBreakIterator() { |
| if (fPOSIXWordBreakIterator == null) |
| fPOSIXWordBreakIterator= BreakIterator.getWordInstance(new Locale("en", "US", "POSIX")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ |
| return fPOSIXWordBreakIterator; |
| } |
| |
| /** |
| * Tries to find the word at the given offset. |
| * |
| * @param document the document |
| * @param offset the offset |
| * @param wordBreakIterator the word break iterator |
| * @return the word or <code>null</code> if none |
| * @since 3.7 |
| */ |
| private IRegion findWord(IDocument document, int offset, BreakIterator wordBreakIterator) { |
| IRegion line; |
| try { |
| line= document.getLineInformationOfOffset(offset); |
| } catch (BadLocationException e) { |
| return null; |
| } |
| |
| if (offset == line.getOffset() + line.getLength()) |
| return null; |
| |
| fDocIter.setDocument(document, line); |
| |
| wordBreakIterator.setText(fDocIter); |
| |
| int start= wordBreakIterator.preceding(offset); |
| if (start == BreakIterator.DONE) |
| start= line.getOffset(); |
| |
| int end= wordBreakIterator.following(offset); |
| if (end == BreakIterator.DONE) |
| end= line.getOffset() + line.getLength(); |
| |
| if (wordBreakIterator.isBoundary(offset)) { |
| if (end - offset > offset - start) |
| start= offset; |
| else |
| end= offset; |
| } |
| |
| if (end == start) |
| return null; |
| |
| int length= end - start; |
| try { |
| // Workaround for ICU bug not treating '.' as word boundary, see http://bugs.icu-project.org/trac/ticket/8371 for details. |
| if (fPOSIXWordBreakIterator != wordBreakIterator && document.get(start, length).indexOf('.') != -1) { |
| IRegion wordRegion= findWord(document, offset, getPOSIXWordBreakIterator()); |
| if (wordRegion != null) { |
| int wordStart= wordRegion.getOffset(); |
| int wordEnd= wordStart + wordRegion.getLength(); |
| // Check that no additional breaks besides '.' are introduced |
| if ((wordStart == start || wordStart > start && document.getChar(wordStart - 1) == '.') && (wordEnd == end || wordEnd < end && document.getChar(wordEnd) == '.')) |
| return wordRegion; |
| } |
| } |
| } catch (BadLocationException e) { |
| // Use previously computed word region |
| } |
| |
| return new Region(start, length); |
| |
| } |
| } |