examples/org.eclipse.ui.examples.undo/Eclipse UI Examples Undo/org/eclipse/ui/examples/undo/ClearBoxesOperation.java

/*******************************************************************************
 * Copyright (c) 2005 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.ui.examples.undo;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.commands.operations.IUndoContext;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.swt.widgets.Canvas;

/**
 * An operation that adds a box.
 */
public class ClearBoxesOperation extends BoxOperation {

	/*
	 * The boxes that are saved after clearing
	 */
	private List savedBoxes = new ArrayList();
	
	public ClearBoxesOperation(String label, IUndoContext context, Boxes boxes, Canvas canvas) {
		super(label, context, boxes, null, canvas);
	}

	/*
	 *  (non-Javadoc)
	 * @see org.eclipse.core.commands.operations.IUndoableOperation#execute(org.eclipse.core.runtime.IProgressMonitor, org.eclipse.core.runtime.IAdaptable)
	 */
	public IStatus execute(IProgressMonitor monitor, IAdaptable info)
			throws ExecutionException {
		savedBoxes = boxes.getBoxes();
		boxes.clear();
		canvas.redraw();
		return Status.OK_STATUS;
	}

	/*
	 *  (non-Javadoc)
	 * @see org.eclipse.core.commands.operations.IUndoableOperation#redo(org.eclipse.core.runtime.IProgressMonitor, org.eclipse.core.runtime.IAdaptable)
	 */
	public IStatus redo(IProgressMonitor monitor, IAdaptable info)
			throws ExecutionException {
		return execute(monitor, info);
	}

	/*
	 *  (non-Javadoc)
	 * @see org.eclipse.core.commands.operations.IUndoableOperation#undo(org.eclipse.core.runtime.IProgressMonitor, org.eclipse.core.runtime.IAdaptable)
	 */
	public IStatus undo(IProgressMonitor monitor, IAdaptable info)
			throws ExecutionException {
		boxes.setBoxes(savedBoxes);
		canvas.redraw();
		return Status.OK_STATUS;
	}

}