/*******************************************************************************
 * Copyright (c) 2005, 2007 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.debug.internal.ui.viewers.update;

import org.eclipse.debug.core.DebugEvent;
import org.eclipse.debug.core.model.IDebugElement;
import org.eclipse.debug.core.model.IDebugTarget;
import org.eclipse.debug.core.model.IStackFrame;

/**
 * Default update for variables view.
 *
 * @since 3.2
 */
public class DefaultVariableViewModelProxy extends EventHandlerModelProxy {

	/**
	 * Root model element for this update policy
	 */
	private IStackFrame fFrame;

	/**
	 * Constructs an update policy on the given target.
	 *
	 * @param target
	 */
	public DefaultVariableViewModelProxy(IStackFrame frame) {
		super();
		fFrame = frame;
	}

	@Override
	public void dispose() {
		super.dispose();
		fFrame = null;
	}

	@Override
	protected DebugEventHandler[] createEventHandlers() {
		return new DebugEventHandler[] { new VariablesViewEventHandler(this, fFrame) };
	}

   /* (non-Javadoc)
    * @see org.eclipse.debug.internal.ui.viewers.update.EventHandlerModelProxy#containsEvent(org.eclipse.debug.core.DebugEvent)
    */
	@Override
	protected synchronized boolean containsEvent(DebugEvent event) {
		if (!isDisposed()) {
	        Object source = event.getSource();
	        if (source instanceof IDebugElement) {
	            IDebugTarget debugTarget = ((IDebugElement) source).getDebugTarget();
	            if (debugTarget != null) {
	            	// a debug target can be null for an IExpression
	            	return debugTarget.equals(fFrame.getDebugTarget());
	            }
	        }
		}
        return false;
    }

}