/*******************************************************************************
* Copyright (c) 2000, 2008 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 com.ibm.icu.text.BreakIterator;
import java.text.CharacterIterator;
/**
* Standard implementation of
* {@link org.eclipse.jface.text.ITextDoubleClickStrategy}.
* <p>
* Selects words using <code>java.text.BreakIterator</code> for the default
* locale.</p>
* <p>
* This class is not intended to be subclassed.
* </p>
*
* @see java.text.BreakIterator
* @noextend This class is not intended to be subclassed by clients.
*/
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();
}
/*
* @see CharacterIterator#first()
*/
public char first() {
fIndex= fOffset;
return current();
}
/*
* @see CharacterIterator#last()
*/
public char last() {
fIndex= fOffset < fEndOffset ? fEndOffset -1 : fEndOffset;
return current();
}
/*
* @see CharacterIterator#current()
*/
public char current() {
if (fOffset <= fIndex && fIndex < fEndOffset) {
try {
return fDocument.getChar(fIndex);
} catch (BadLocationException x) {
}
}
return DONE;
}
/*
* @see CharacterIterator#next()
*/
public char next() {
++fIndex;
int end= getEndIndex();
if (fIndex >= end) {
fIndex= end;
return DONE;
}
return current();
}
/*
* @see CharacterIterator#previous()
*/
public char previous() {
if (fIndex == fOffset)
return DONE;
if (fIndex > fOffset)
-- fIndex;
return current();
}
/*
* @see CharacterIterator#setIndex(int)
*/
public char setIndex(int index) {
fIndex= index;
return current();
}
/*
* @see CharacterIterator#getBeginIndex()
*/
public int getBeginIndex() {
return fOffset;
}
/*
* @see CharacterIterator#getEndIndex()
*/
public int getEndIndex() {
return fEndOffset;
}
/*
* @see CharacterIterator#getIndex()
*/
public int getIndex() {
return fIndex;
}
/*
* @see CharacterIterator#clone()
*/
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();
/**
* Creates a new default text double click strategy.
*/
public DefaultTextDoubleClickStrategy() {
super();
}
/*
* @see org.eclipse.jface.text.ITextDoubleClickStrategy#doubleClicked(org.eclipse.jface.text.ITextViewer)
*/
public void doubleClicked(ITextViewer text) {
int position= text.getSelectedRange().x;
if (position < 0)
return;
try {
IDocument document= text.getDocument();
IRegion line= document.getLineInformationOfOffset(position);
if (position == line.getOffset() + line.getLength())
return;
fDocIter.setDocument(document, line);
BreakIterator breakIter= BreakIterator.getWordInstance();
breakIter.setText(fDocIter);
int start= breakIter.preceding(position);
if (start == BreakIterator.DONE)
start= line.getOffset();
int end= breakIter.following(position);
if (end == BreakIterator.DONE)
end= line.getOffset() + line.getLength();
if (breakIter.isBoundary(position)) {
if (end - position > position- start)
start= position;
else
end= position;
}
if (start != end)
text.setSelectedRange(start, end - start);
} catch (BadLocationException x) {
}
}
}