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 * TickUnit.java 029 * ------------- 030 * (C) Copyright 2001-2005, by Object Refinery Limited. 031 * 032 * Original Author: David Gilbert (for Object Refinery Limited); 033 * Contributor(s): -; 034 * 035 * $Id: TickUnit.java,v 1.3.2.2 2005/10/25 20:37:34 mungady Exp $ 036 * 037 * Changes (from 19-Dec-2001) 038 * -------------------------- 039 * 19-Dec-2001 : Added standard header (DG); 040 * 01-May-2002 : Changed the unit size from Number to double (DG); 041 * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG); 042 * 08-Nov-2002 : Moved to new package com.jrefinery.chart.axis (DG); 043 * 26-Mar-2003 : Implemented Serializable (DG); 044 * 05-Sep-2005 : Implemented hashCode(), thanks to Thomas Morgner (DG); 045 * 046 */ 047 048 package org.jfree.chart.axis; 049 050 import java.io.Serializable; 051 052 /** 053 * Base class representing a tick unit. This determines the spacing of the 054 * tick marks on an axis. 055 * <P> 056 * This class (and any subclasses) should be immutable, the reason being that 057 * ORDERED collections of tick units are maintained and if one instance can be 058 * changed, it may destroy the order of the collection that it belongs to. 059 * In addition, if the implementations are immutable, they can belong to 060 * multiple collections. 061 * 062 * @see ValueAxis 063 */ 064 public abstract class TickUnit implements Comparable, Serializable { 065 066 /** For serialization. */ 067 private static final long serialVersionUID = 510179855057013974L; 068 069 /** The size of the tick unit. */ 070 private double size; 071 072 /** 073 * Constructs a new tick unit. 074 * 075 * @param size the tick unit size. 076 */ 077 public TickUnit(double size) { 078 this.size = size; 079 } 080 081 /** 082 * Returns the size of the tick unit. 083 * 084 * @return The size of the tick unit. 085 */ 086 public double getSize() { 087 return this.size; 088 } 089 090 /** 091 * Converts the supplied value to a string. 092 * <P> 093 * Subclasses may implement special formatting by overriding this method. 094 * 095 * @param value the data value. 096 * 097 * @return Value as string. 098 */ 099 public String valueToString(double value) { 100 return String.valueOf(value); 101 } 102 103 /** 104 * Compares this tick unit to an arbitrary object. 105 * 106 * @param object the object to compare against. 107 * 108 * @return <code>1</code> if the size of the other object is less than this, 109 * <code>0</code> if both have the same size and <code>-1</code> this 110 * size is less than the others. 111 */ 112 public int compareTo(Object object) { 113 114 if (object instanceof TickUnit) { 115 TickUnit other = (TickUnit) object; 116 if (this.size > other.getSize()) { 117 return 1; 118 } 119 else if (this.size < other.getSize()) { 120 return -1; 121 } 122 else { 123 return 0; 124 } 125 } 126 else { 127 return -1; 128 } 129 130 } 131 132 /** 133 * Tests this unit for equality with another object. 134 * 135 * @param obj the object. 136 * 137 * @return <code>true</code> or <code>false</code>. 138 */ 139 public boolean equals(Object obj) { 140 141 if (obj == null) { 142 return false; 143 } 144 if (obj == this) { 145 return true; 146 } 147 if (obj instanceof TickUnit) { 148 TickUnit tu = (TickUnit) obj; 149 return this.size == tu.size; 150 } 151 return false; 152 153 } 154 155 /** 156 * Returns a hash code for this instance. 157 * 158 * @return A hash code. 159 */ 160 public int hashCode() { 161 final long temp = size != +0.0d ? Double.doubleToLongBits(size) : 0L; 162 return (int) (temp ^ (temp >>> 32)); 163 } 164 165 }