001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * ---------------
028 * EmptyBlock.java
029 * ---------------
030 * (C) Copyright 2004, 2005, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: EmptyBlock.java,v 1.4.2.1 2005/10/25 20:39:38 mungady Exp $
036 *
037 * Changes:
038 * --------
039 * 22-Oct-2004 : Version 1 (DG);
040 * 04-Feb-2005 : Now cloneable and serializable (DG);
041 * 20-Apr-2005 : Added new draw() method (DG);
042 *
043 */
044
045 package org.jfree.chart.block;
046
047 import java.awt.Graphics2D;
048 import java.awt.geom.Rectangle2D;
049 import java.io.Serializable;
050
051 import org.jfree.util.PublicCloneable;
052
053 /**
054 * An empty block with a fixed size.
055 */
056 public class EmptyBlock extends AbstractBlock
057 implements Block, Cloneable, PublicCloneable,
058 Serializable {
059
060 /** For serialization. */
061 private static final long serialVersionUID = -4083197869412648579L;
062
063 /**
064 * Creates a new block with the specified width and height.
065 *
066 * @param width the width.
067 * @param height the height.
068 */
069 public EmptyBlock(double width, double height) {
070 setWidth(width);
071 setHeight(height);
072 }
073
074 /**
075 * Draws the block. Since the block is empty, this method does nothing.
076 *
077 * @param g2 the graphics device.
078 * @param area the area.
079 */
080 public void draw(Graphics2D g2, Rectangle2D area) {
081 // do nothing, we're empty
082 }
083
084 /**
085 * Draws the block within the specified area. Since the block is empty,
086 * this method does nothing.
087 *
088 * @param g2 the graphics device.
089 * @param area the area.
090 * @param params ignored (<code>null</code> permitted).
091 *
092 * @return Always <code>null</code>.
093 */
094 public Object draw(Graphics2D g2, Rectangle2D area, Object params) {
095 return null;
096 }
097
098 /**
099 * Returns a clone of the block.
100 *
101 * @return A clone.
102 *
103 * @throws CloneNotSupportedException if there is a problem cloning.
104 */
105 public Object clone() throws CloneNotSupportedException {
106 return super.clone();
107 }
108
109 }