001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, 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 * DatasetRenderingOrder.java
029 * --------------------------
030 * (C) Copyright 2003-2008, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * Changes:
036 * --------
037 * 02-May-2003 : Version 1 (DG);
038 * 02-Jun-2004 : Changed 'STANDARD' --> 'FORWARD' (DG);
039 * 21-Nov-2007 : Implemented hashCode() (DG);
040 *
041 */
042
043 package org.jfree.chart.plot;
044
045 import java.io.ObjectStreamException;
046 import java.io.Serializable;
047
048 /**
049 * Defines the tokens that indicate the rendering order for datasets in a
050 * {@link org.jfree.chart.plot.CategoryPlot} or an
051 * {@link org.jfree.chart.plot.XYPlot}.
052 */
053 public final class DatasetRenderingOrder implements Serializable {
054
055 /** For serialization. */
056 private static final long serialVersionUID = -600593412366385072L;
057
058 /**
059 * Render datasets in the order 0, 1, 2, ..., N-1, where N is the number
060 * of datasets.
061 */
062 public static final DatasetRenderingOrder FORWARD
063 = new DatasetRenderingOrder("DatasetRenderingOrder.FORWARD");
064
065 /**
066 * Render datasets in the order N-1, N-2, ..., 2, 1, 0, where N is the
067 * number of datasets.
068 */
069 public static final DatasetRenderingOrder REVERSE
070 = new DatasetRenderingOrder("DatasetRenderingOrder.REVERSE");
071
072 /** The name. */
073 private String name;
074
075 /**
076 * Private constructor.
077 *
078 * @param name the name.
079 */
080 private DatasetRenderingOrder(String name) {
081 this.name = name;
082 }
083
084 /**
085 * Returns a string representing the object.
086 *
087 * @return The string (never <code>null</code>).
088 */
089 public String toString() {
090 return this.name;
091 }
092
093 /**
094 * Returns <code>true</code> if this object is equal to the specified
095 * object, and <code>false</code> otherwise.
096 *
097 * @param obj the object (<code>null</code> permitted).
098 *
099 * @return A boolean.
100 */
101 public boolean equals(Object obj) {
102 if (this == obj) {
103 return true;
104 }
105 if (!(obj instanceof DatasetRenderingOrder)) {
106 return false;
107 }
108 DatasetRenderingOrder order = (DatasetRenderingOrder) obj;
109 if (!this.name.equals(order.toString())) {
110 return false;
111 }
112 return true;
113 }
114
115 /**
116 * Returns a hash code for this instance.
117 *
118 * @return A hash code.
119 */
120 public int hashCode() {
121 return this.name.hashCode();
122 }
123
124 /**
125 * Ensures that serialization returns the unique instances.
126 *
127 * @return The object.
128 *
129 * @throws ObjectStreamException if there is a problem.
130 */
131 private Object readResolve() throws ObjectStreamException {
132 if (this.equals(DatasetRenderingOrder.FORWARD)) {
133 return DatasetRenderingOrder.FORWARD;
134 }
135 else if (this.equals(DatasetRenderingOrder.REVERSE)) {
136 return DatasetRenderingOrder.REVERSE;
137 }
138 return null;
139 }
140
141 }