001 /* =========================================================== 002 * JFreeChart : a free chart library for the Java(tm) platform 003 * =========================================================== 004 * 005 * (C) Copyright 2000-2007, 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 * GrayPaintScale.java 029 * ------------------- 030 * (C) Copyright 2006, 2007, by Object Refinery Limited. 031 * 032 * Original Author: David Gilbert (for Object Refinery Limited); 033 * Contributor(s): -; 034 * 035 * $Id: GrayPaintScale.java,v 1.1.2.1 2007/01/31 14:15:16 mungady Exp $ 036 * 037 * Changes 038 * ------- 039 * 05-Jul-2006 : Version 1 (DG); 040 * 31-Jan-2007 : Renamed min and max to lowerBound and upperBound (DG); 041 * 042 */ 043 044 package org.jfree.chart.renderer; 045 046 import java.awt.Color; 047 import java.awt.Paint; 048 import java.io.Serializable; 049 050 import org.jfree.util.PublicCloneable; 051 052 /** 053 * A paint scale that returns shades of gray. 054 * 055 * @since 1.0.4 056 */ 057 public class GrayPaintScale 058 implements PaintScale, PublicCloneable, Serializable { 059 060 /** The lower bound. */ 061 private double lowerBound; 062 063 /** The upper bound. */ 064 private double upperBound; 065 066 /** 067 * Creates a new <code>GrayPaintScale</code> instance with default values. 068 */ 069 public GrayPaintScale() { 070 this(0.0, 1.0); 071 } 072 073 /** 074 * Creates a new paint scale for values in the specified range. 075 * 076 * @param lowerBound the lower bound. 077 * @param upperBound the upper bound. 078 */ 079 public GrayPaintScale(double lowerBound, double upperBound) { 080 if (lowerBound >= upperBound) { 081 throw new IllegalArgumentException( 082 "Requires lowerBound < upperBound."); 083 } 084 this.lowerBound = lowerBound; 085 this.upperBound = upperBound; 086 } 087 088 /** 089 * Returns the lower bound. 090 * 091 * @return The lower bound. 092 */ 093 public double getLowerBound() { 094 return this.lowerBound; 095 } 096 097 /** 098 * Returns the upper bound. 099 * 100 * @return The upper bound. 101 */ 102 public double getUpperBound() { 103 return this.upperBound; 104 } 105 106 /** 107 * Returns a paint for the specified value. 108 * 109 * @param value the value. 110 * 111 * @return A paint for the specified value. 112 */ 113 public Paint getPaint(double value) { 114 double v = Math.max(value, this.lowerBound); 115 v = Math.min(v, this.upperBound); 116 int g = (int) ((value - this.lowerBound) / (this.upperBound 117 - this.lowerBound) * 255.0); 118 return new Color(g, g, g); 119 } 120 121 /** 122 * Tests this <code>GrayPaintScale</code> instance for equality with an 123 * arbitrary object. This method returns <code>true</code> if and only 124 * if: 125 * <ul> 126 * <li><code>obj</code> is not <code>null</code>;</li> 127 * <li><code>obj</code> is an instance of <code>GrayPaintScale</code>;</li> 128 * </ul> 129 * 130 * @param obj the object (<code>null</code> permitted). 131 * 132 * @return A boolean. 133 */ 134 public boolean equals(Object obj) { 135 if (obj == this) { 136 return true; 137 } 138 if (!(obj instanceof GrayPaintScale)) { 139 return false; 140 } 141 GrayPaintScale that = (GrayPaintScale) obj; 142 if (this.lowerBound != that.lowerBound) { 143 return false; 144 } 145 if (this.upperBound != that.upperBound) { 146 return false; 147 } 148 return true; 149 } 150 151 /** 152 * Returns a clone of this <code>GrayPaintScale</code> instance. 153 * 154 * @return A clone. 155 * 156 * @throws CloneNotSupportedException if there is a problem cloning this 157 * instance. 158 */ 159 public Object clone() throws CloneNotSupportedException { 160 return super.clone(); 161 } 162 163 }