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 * AxisLocation.java
029 * -----------------
030 * (C) Copyright 2003-2008, by Object Refinery Limited and Contributors.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): Nick Guenther;
034 *
035 * Changes:
036 * --------
037 * 02-May-2003 : Version 1 (DG);
038 * 03-Jul-2003 : Added isTopOrBottom() and isLeftOrRight() methods (DG);
039 * 13-Aug-2003 : Fixed readResolve() bug (id=788202) (DG);
040 * 24-Mar-2004 : Added static getOpposite() method (DG);
041 * ------------- JFREECHART 1.0.x ---------------------------------------------
042 * 22-Mar-2007 : Added getOpposite() method, suggested by Nick Guenther (DG);
043 *
044 */
045
046 package org.jfree.chart.axis;
047
048 import java.io.ObjectStreamException;
049 import java.io.Serializable;
050
051 /**
052 * Used to indicate the location of an axis on a 2D plot, prior to knowing the
053 * orientation of the plot.
054 */
055 public final class AxisLocation implements Serializable {
056
057 /** For serialization. */
058 private static final long serialVersionUID = -3276922179323563410L;
059
060 /** Axis at the top or left. */
061 public static final AxisLocation TOP_OR_LEFT = new AxisLocation(
062 "AxisLocation.TOP_OR_LEFT");
063
064 /** Axis at the top or right. */
065 public static final AxisLocation TOP_OR_RIGHT = new AxisLocation(
066 "AxisLocation.TOP_OR_RIGHT");
067
068 /** Axis at the bottom or left. */
069 public static final AxisLocation BOTTOM_OR_LEFT = new AxisLocation(
070 "AxisLocation.BOTTOM_OR_LEFT");
071
072 /** Axis at the bottom or right. */
073 public static final AxisLocation BOTTOM_OR_RIGHT = new AxisLocation(
074 "AxisLocation.BOTTOM_OR_RIGHT");
075
076 /** The name. */
077 private String name;
078
079 /**
080 * Private constructor.
081 *
082 * @param name the name.
083 */
084 private AxisLocation(String name) {
085 this.name = name;
086 }
087
088 /**
089 * Returns the location that is opposite to this location.
090 *
091 * @return The opposite location.
092 *
093 * @since 1.0.5
094 */
095 public AxisLocation getOpposite() {
096 return getOpposite(this);
097 }
098
099 /**
100 * Returns a string representing the object.
101 *
102 * @return The string.
103 */
104 public String toString() {
105 return this.name;
106 }
107
108 /**
109 * Returns <code>true</code> if this object is equal to the specified
110 * object, and <code>false</code> otherwise.
111 *
112 * @param obj the other object (<code>null</code> permitted).
113 *
114 * @return A boolean.
115 */
116 public boolean equals(Object obj) {
117
118 if (this == obj) {
119 return true;
120 }
121 if (!(obj instanceof AxisLocation)) {
122 return false;
123 }
124 AxisLocation location = (AxisLocation) obj;
125 if (!this.name.equals(location.toString())) {
126 return false;
127 }
128 return true;
129
130 }
131
132 /**
133 * Returns the location that is opposite to the supplied location.
134 *
135 * @param location the location (<code>null</code> not permitted).
136 *
137 * @return The opposite location.
138 */
139 public static AxisLocation getOpposite(AxisLocation location) {
140 if (location == null) {
141 throw new IllegalArgumentException("Null 'location' argument.");
142 }
143 AxisLocation result = null;
144 if (location == AxisLocation.TOP_OR_LEFT) {
145 result = AxisLocation.BOTTOM_OR_RIGHT;
146 }
147 else if (location == AxisLocation.TOP_OR_RIGHT) {
148 result = AxisLocation.BOTTOM_OR_LEFT;
149 }
150 else if (location == AxisLocation.BOTTOM_OR_LEFT) {
151 result = AxisLocation.TOP_OR_RIGHT;
152 }
153 else if (location == AxisLocation.BOTTOM_OR_RIGHT) {
154 result = AxisLocation.TOP_OR_LEFT;
155 }
156 else {
157 throw new IllegalStateException("AxisLocation not recognised.");
158 }
159 return result;
160 }
161
162 /**
163 * Ensures that serialization returns the unique instances.
164 *
165 * @return The object.
166 *
167 * @throws ObjectStreamException if there is a problem.
168 */
169 private Object readResolve() throws ObjectStreamException {
170 if (this.equals(AxisLocation.TOP_OR_RIGHT)) {
171 return AxisLocation.TOP_OR_RIGHT;
172 }
173 else if (this.equals(AxisLocation.BOTTOM_OR_RIGHT)) {
174 return AxisLocation.BOTTOM_OR_RIGHT;
175 }
176 else if (this.equals(AxisLocation.TOP_OR_LEFT)) {
177 return AxisLocation.TOP_OR_LEFT;
178 }
179 else if (this.equals(AxisLocation.BOTTOM_OR_LEFT)) {
180 return AxisLocation.BOTTOM_OR_LEFT;
181 }
182 return null;
183 }
184
185 }