/*******************************************************************************
* Copyright (c) 2011 Wind River Systems 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:
* Wind River Systems - initial API and implementation
*******************************************************************************/
package org.eclipse.debug.internal.ui.viewers.model.provisional;
import org.eclipse.jface.viewers.ViewerFilter;
/**
* Viewer filter for the Tree Model Viewer which allows more efficient filtering
* in the lazy viewer.
* <p>
* The standard {@link ViewerFilter} class must be applied to all elements in the
* tree, thus forcing the lazy viewer to retrieve all children of all elements and
* defeating the lazy loading behavior. This class adds an {@link #isApplicable(ITreeModelViewer, Object)}
* method, which can be used by the filter to discern which parent elements the
* filter should apply to.
* </p>
*
* @since 3.8
*/
abstract public class TreeModelViewerFilter extends ViewerFilter {
/**
* Determines whether the filter applies to the given parent element.
* @return Returns true if the viewer should use the given filter on the
* given element.
* @param viewer The viewer that is using this filter to select elements.
* @param parentElement Parent element to check filter for.
*/
abstract public boolean isApplicable(ITreeModelViewer viewer, Object parentElement);
}