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 * CategoryAnchor.java
029 * -------------------
030 * (C) Copyright 2003-2007, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * Changes:
036 * --------
037 * 04-Jul-2003 : Version 1 (DG);
038 *
039 */
040
041 package org.jfree.chart.axis;
042
043 import java.io.ObjectStreamException;
044 import java.io.Serializable;
045
046 /**
047 * Used to indicate one of three positions within a category:
048 * <code>START</code>, <code>MIDDLE</code> and <code>END</code>.
049 */
050 public final class CategoryAnchor implements Serializable {
051
052 /** For serialization. */
053 private static final long serialVersionUID = -2604142742210173810L;
054
055 /** Start of period. */
056 public static final CategoryAnchor START
057 = new CategoryAnchor("CategoryAnchor.START");
058
059 /** Middle of period. */
060 public static final CategoryAnchor MIDDLE
061 = new CategoryAnchor("CategoryAnchor.MIDDLE");
062
063 /** End of period. */
064 public static final CategoryAnchor END
065 = new CategoryAnchor("CategoryAnchor.END");
066
067 /** The name. */
068 private String name;
069
070 /**
071 * Private constructor.
072 *
073 * @param name the name.
074 */
075 private CategoryAnchor(String name) {
076 this.name = name;
077 }
078
079 /**
080 * Returns a string representing the object.
081 *
082 * @return The string.
083 */
084 public String toString() {
085 return this.name;
086 }
087
088 /**
089 * Returns <code>true</code> if this object is equal to the specified
090 * object, and <code>false</code> otherwise.
091 *
092 * @param obj the other object.
093 *
094 * @return A boolean.
095 */
096 public boolean equals(Object obj) {
097
098 if (this == obj) {
099 return true;
100 }
101 if (!(obj instanceof CategoryAnchor)) {
102 return false;
103 }
104 CategoryAnchor position = (CategoryAnchor) obj;
105 if (!this.name.equals(position.toString())) {
106 return false;
107 }
108 return true;
109
110 }
111
112 /**
113 * Ensures that serialization returns the unique instances.
114 *
115 * @return The object.
116 *
117 * @throws ObjectStreamException if there is a problem.
118 */
119 private Object readResolve() throws ObjectStreamException {
120 if (this.equals(CategoryAnchor.START)) {
121 return CategoryAnchor.START;
122 }
123 else if (this.equals(CategoryAnchor.MIDDLE)) {
124 return CategoryAnchor.MIDDLE;
125 }
126 else if (this.equals(CategoryAnchor.END)) {
127 return CategoryAnchor.END;
128 }
129 return null;
130 }
131
132 }