/*******************************************************************************
* Copyright (c) 2005, 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 java.util.Iterator;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.ISourceViewerExtension2;
/**
* Standard implementation of {@link org.eclipse.jface.text.ITextHover}.
*
* @since 3.2
*/
public class DefaultTextHover implements ITextHover {
/** This hover's source viewer */
private ISourceViewer fSourceViewer;
/**
* Creates a new annotation hover.
*
* @param sourceViewer this hover's annotation model
*/
public DefaultTextHover(ISourceViewer sourceViewer) {
Assert.isNotNull(sourceViewer);
fSourceViewer= sourceViewer;
}
/*
* @see org.eclipse.jface.text.ITextHover#getHoverInfo(org.eclipse.jface.text.ITextViewer, org.eclipse.jface.text.IRegion)
*/
public String getHoverInfo(ITextViewer textViewer, IRegion hoverRegion) {
IAnnotationModel model= getAnnotationModel(fSourceViewer);
if (model == null)
return null;
Iterator e= model.getAnnotationIterator();
while (e.hasNext()) {
Annotation a= (Annotation) e.next();
if (isIncluded(a)) {
Position p= model.getPosition(a);
if (p != null && p.overlapsWith(hoverRegion.getOffset(), hoverRegion.getLength())) {
String msg= a.getText();
if (msg != null && msg.trim().length() > 0)
return msg;
}
}
}
return null;
}
/*
* @see org.eclipse.jface.text.ITextHover#getHoverRegion(org.eclipse.jface.text.ITextViewer, int)
*/
public IRegion getHoverRegion(ITextViewer textViewer, int offset) {
return findWord(textViewer.getDocument(), offset);
}
/**
* Tells whether the annotation should be included in
* the computation.
*
* @param annotation the annotation to test
* @return <code>true</code> if the annotation is included in the computation
*/
protected boolean isIncluded(Annotation annotation) {
return true;
}
private IAnnotationModel getAnnotationModel(ISourceViewer viewer) {
if (viewer instanceof ISourceViewerExtension2) {
ISourceViewerExtension2 extension= (ISourceViewerExtension2) viewer;
return extension.getVisualAnnotationModel();
}
return viewer.getAnnotationModel();
}
private IRegion findWord(IDocument document, int offset) {
int start= -2;
int end= -1;
try {
int pos= offset;
char c;
while (pos >= 0) {
c= document.getChar(pos);
if (!Character.isUnicodeIdentifierPart(c))
break;
--pos;
}
start= pos;
pos= offset;
int length= document.getLength();
while (pos < length) {
c= document.getChar(pos);
if (!Character.isUnicodeIdentifierPart(c))
break;
++pos;
}
end= pos;
} catch (BadLocationException x) {
}
if (start >= -1 && end > -1) {
if (start == offset && end == offset)
return new Region(offset, 0);
else if (start == offset)
return new Region(start, end - start);
else
return new Region(start + 1, end - start - 1);
}
return null;
}
}