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 * XYDataItem.java 029 * --------------- 030 * (C) Copyright 2003-2005, by Object Refinery Limited. 031 * 032 * Original Author: David Gilbert (for Object Refinery Limited); 033 * Contributor(s): -; 034 * 035 * $Id: XYDataItem.java,v 1.6.2.1 2005/10/25 21:36:51 mungady Exp $ 036 * 037 * Changes 038 * ------- 039 * 05-Aug-2003 : Renamed XYDataPair --> XYDataItem (DG); 040 * 03-Feb-2004 : Fixed bug in equals() method (DG); 041 * 21-Feb-2005 : Added setY(double) method (DG); 042 * 043 */ 044 045 package org.jfree.data.xy; 046 047 import java.io.Serializable; 048 049 import org.jfree.util.ObjectUtilities; 050 051 /** 052 * Represents one (x, y) data item for an {@link XYSeries}. 053 */ 054 public class XYDataItem implements Cloneable, Comparable, Serializable { 055 056 private static final long serialVersionUID = 2751513470325494890L; 057 058 /** The x-value. */ 059 private Number x; 060 061 /** The y-value. */ 062 private Number y; 063 064 /** 065 * Constructs a new data item. 066 * 067 * @param x the x-value (<code>null</code> NOT permitted). 068 * @param y the y-value (<code>null</code> permitted). 069 */ 070 public XYDataItem(Number x, Number y) { 071 if (x == null) { 072 throw new IllegalArgumentException("Null 'x' argument."); 073 } 074 this.x = x; 075 this.y = y; 076 } 077 078 /** 079 * Constructs a new data item. 080 * 081 * @param x the x-value. 082 * @param y the y-value. 083 */ 084 public XYDataItem(double x, double y) { 085 this(new Double(x), new Double(y)); 086 } 087 088 /** 089 * Returns the x-value. 090 * 091 * @return The x-value (never <code>null</code>). 092 */ 093 public Number getX() { 094 return this.x; 095 } 096 097 /** 098 * Returns the y-value. 099 * 100 * @return The y-value (possibly <code>null</code>). 101 */ 102 public Number getY() { 103 return this.y; 104 } 105 106 /** 107 * Sets the y-value for this data item. Note that there is no 108 * corresponding method to change the x-value. 109 * 110 * @param y the new y-value. 111 */ 112 public void setY(double y) { 113 setY(new Double(y)); 114 } 115 116 /** 117 * Sets the y-value for this data item. Note that there is no 118 * corresponding method to change the x-value. 119 * 120 * @param y the new y-value (<code>null</code> permitted). 121 */ 122 public void setY(Number y) { 123 this.y = y; 124 } 125 126 /** 127 * Returns an integer indicating the order of this object relative to 128 * another object. 129 * <P> 130 * For the order we consider only the x-value: 131 * negative == "less-than", zero == "equal", positive == "greater-than". 132 * 133 * @param o1 the object being compared to. 134 * 135 * @return An integer indicating the order of this data pair object 136 * relative to another object. 137 */ 138 public int compareTo(Object o1) { 139 140 int result; 141 142 // CASE 1 : Comparing to another TimeSeriesDataPair object 143 // ------------------------------------------------------- 144 if (o1 instanceof XYDataItem) { 145 XYDataItem dataItem = (XYDataItem) o1; 146 double compare = this.x.doubleValue() 147 - dataItem.getX().doubleValue(); 148 if (compare > 0.0) { 149 result = 1; 150 } 151 else { 152 if (compare < 0.0) { 153 result = -1; 154 } 155 else { 156 result = 0; 157 } 158 } 159 } 160 161 // CASE 2 : Comparing to a general object 162 // --------------------------------------------- 163 else { 164 // consider time periods to be ordered after general objects 165 result = 1; 166 } 167 168 return result; 169 170 } 171 172 /** 173 * Returns a clone of this object. 174 * 175 * @return A clone. 176 * 177 * @throws CloneNotSupportedException not thrown by this class, but 178 * subclasses may differ. 179 */ 180 public Object clone() throws CloneNotSupportedException { 181 return super.clone(); 182 } 183 184 /** 185 * Tests if this object is equal to another. 186 * 187 * @param obj the object to test against for equality (<code>null</code> 188 * permitted). 189 * 190 * @return A boolean. 191 */ 192 public boolean equals(Object obj) { 193 if (obj == this) { 194 return true; 195 } 196 if (!(obj instanceof XYDataItem)) { 197 return false; 198 } 199 XYDataItem that = (XYDataItem) obj; 200 if (!this.x.equals(that.x)) { 201 return false; 202 } 203 if (!ObjectUtilities.equal(this.y, that.y)) { 204 return false; 205 } 206 return true; 207 } 208 209 /** 210 * Returns a hash code. 211 * 212 * @return A hash code. 213 */ 214 public int hashCode() { 215 int result; 216 result = this.x.hashCode(); 217 result = 29 * result + (this.y != null ? this.y.hashCode() : 0); 218 return result; 219 } 220 221 }