/*******************************************************************************
 * Copyright (c) 2000, 2010 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.draw2d;

import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Insets;
import org.eclipse.draw2d.geometry.Rectangle;

/**
 * Provides generic support for borders.
 * 
 * @author hudsonr
 */
public abstract class AbstractBorder implements Border {

	private static final Dimension EMPTY = new Dimension();

	/** A temporary Rectangle */
	protected static Rectangle tempRect = new Rectangle();

	/**
	 * Returns a temporary rectangle representing the figure's bounds cropped by
	 * the specified insets. This method exists for convenience and performance;
	 * the method does not new any Objects and returns a rectangle which the
	 * caller can manipulate.
	 * 
	 * @since 2.0
	 * @param figure
	 *            Figure for which the paintable rectangle is needed
	 * @param insets
	 *            The insets
	 * @return The paintable region on the Figure f
	 */
	protected static final Rectangle getPaintRectangle(IFigure figure,
			Insets insets) {
		tempRect.setBounds(figure.getBounds());
		return tempRect.crop(insets);
	}

	/**
	 * @see org.eclipse.draw2d.Border#getPreferredSize(IFigure)
	 */
	public Dimension getPreferredSize(IFigure f) {
		return EMPTY;
	}

	/**
	 * @see org.eclipse.draw2d.Border#isOpaque()
	 */
	public boolean isOpaque() {
		return false;
	}

}
