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 }