/*******************************************************************************
* Copyright (c) 2000, 2012 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 (JDT)
* Tomasz Wesolowski - port from JDT
*******************************************************************************/
package org.eclipse.cdt.internal.ui.editor;
import java.util.Stack;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.cdt.core.model.ISourceRange;
public class SelectionHistory {
private Stack<ISourceRange> fHistory;
private CEditor fEditor;
private ISelectionChangedListener fSelectionListener;
private int fSelectionChangeListenerCounter;
public SelectionHistory(CEditor editor) {
Assert.isNotNull(editor);
fEditor= editor;
fHistory= new Stack<ISourceRange>();
fSelectionListener= new ISelectionChangedListener() {
@Override
public void selectionChanged(SelectionChangedEvent event) {
if (fSelectionChangeListenerCounter == 0)
flush();
}
};
fEditor.getSelectionProvider().addSelectionChangedListener(fSelectionListener);
}
public boolean isEmpty() {
return fHistory.isEmpty();
}
public void remember(ISourceRange range) {
fHistory.push(range);
}
public ISourceRange getLast() {
if (isEmpty())
return null;
ISourceRange result= fHistory.pop();
return result;
}
public void flush() {
if (fHistory.isEmpty())
return;
fHistory.clear();
}
public void ignoreSelectionChanges() {
fSelectionChangeListenerCounter++;
}
public void listenToSelectionChanges() {
fSelectionChangeListenerCounter--;
}
public void dispose() {
fEditor.getSelectionProvider().removeSelectionChangedListener(fSelectionListener);
}
}