Frames | No Frames |
1: /* =========================================================== 2: * JFreeChart : a free chart library for the Java(tm) platform 3: * =========================================================== 4: * 5: * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors. 6: * 7: * Project Info: http://www.jfree.org/jfreechart/index.html 8: * 9: * This library is free software; you can redistribute it and/or modify it 10: * under the terms of the GNU Lesser General Public License as published by 11: * the Free Software Foundation; either version 2.1 of the License, or 12: * (at your option) any later version. 13: * 14: * This library is distributed in the hope that it will be useful, but 15: * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 16: * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 17: * License for more details. 18: * 19: * You should have received a copy of the GNU Lesser General Public 20: * License along with this library; if not, write to the Free Software 21: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 22: * USA. 23: * 24: * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 25: * in the United States and other countries.] 26: * 27: * --------------------------- 28: * StandardTickUnitSource.java 29: * --------------------------- 30: * (C) Copyright 2003-2007, by Object Refinery Limited. 31: * 32: * Original Author: David Gilbert (for Object Refinery Limited); 33: * Contributor(s): -; 34: * 35: * Changes 36: * ------- 37: * 23-Sep-2003 : Version 1 (DG); 38: * 25-Oct-2007 : Implemented Serializable and equals() method (DG); 39: * 40: */ 41: 42: package org.jfree.chart.axis; 43: 44: import java.io.Serializable; 45: import java.text.DecimalFormat; 46: 47: /** 48: * A source that can used by the {@link NumberAxis} class to obtain a 49: * suitable {@link TickUnit}. Instances of this class are {@link Serializable} 50: * from version 1.0.7 onwards. Cloning is not supported, because instances 51: * are immutable. 52: */ 53: public class StandardTickUnitSource implements TickUnitSource, Serializable { 54: 55: /** Constant for log(10.0). */ 56: private static final double LOG_10_VALUE = Math.log(10.0); 57: 58: /** 59: * Default constructor. 60: */ 61: public StandardTickUnitSource() { 62: super(); 63: } 64: 65: /** 66: * Returns a tick unit that is larger than the supplied unit. 67: * 68: * @param unit the unit (<code>null</code> not permitted). 69: * 70: * @return A tick unit that is larger than the supplied unit. 71: */ 72: public TickUnit getLargerTickUnit(TickUnit unit) { 73: double x = unit.getSize(); 74: double log = Math.log(x) / LOG_10_VALUE; 75: double higher = Math.ceil(log); 76: return new NumberTickUnit(Math.pow(10, higher), 77: new DecimalFormat("0.0E0")); 78: } 79: 80: /** 81: * Returns the tick unit in the collection that is greater than or equal 82: * to (in size) the specified unit. 83: * 84: * @param unit the unit (<code>null</code> not permitted). 85: * 86: * @return A unit from the collection. 87: */ 88: public TickUnit getCeilingTickUnit(TickUnit unit) { 89: return getLargerTickUnit(unit); 90: } 91: 92: /** 93: * Returns the tick unit in the collection that is greater than or equal 94: * to the specified size. 95: * 96: * @param size the size. 97: * 98: * @return A unit from the collection. 99: */ 100: public TickUnit getCeilingTickUnit(double size) { 101: double log = Math.log(size) / LOG_10_VALUE; 102: double higher = Math.ceil(log); 103: return new NumberTickUnit(Math.pow(10, higher), 104: new DecimalFormat("0.0E0")); 105: } 106: 107: /** 108: * Tests this instance for equality with an arbitrary object. 109: * 110: * @param obj the object (<code>null</code> permitted). 111: * 112: * @return A boolean. 113: */ 114: public boolean equals(Object obj) { 115: if (obj == this) { 116: return true; 117: } 118: return (obj instanceof StandardTickUnitSource); 119: } 120: 121: /** 122: * Returns a hash code for this instance. 123: * 124: * @return A hash code. 125: */ 126: public int hashCode() { 127: return 0; 128: } 129: 130: }