001 /* ========================================================================
002 * JCommon : a free general purpose class 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/jcommon/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 * RectangleEdge
029 * -------------
030 * (C) Copyright 2003-2005, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: RectangleEdge.java,v 1.4 2005/10/18 13:18:34 mungady Exp $
036 *
037 * Changes:
038 * --------
039 * 14-Jul-2003 (DG);
040 *
041 */
042
043 package org.jfree.ui;
044
045 import java.awt.geom.Rectangle2D;
046 import java.io.ObjectStreamException;
047 import java.io.Serializable;
048
049 /**
050 * Used to indicate the edge of a rectangle.
051 *
052 * @author David Gilbert
053 */
054 public final class RectangleEdge implements Serializable {
055
056 /** For serialization. */
057 private static final long serialVersionUID = -7400988293691093548L;
058
059 /** Top. */
060 public static final RectangleEdge TOP
061 = new RectangleEdge("RectangleEdge.TOP");
062
063 /** Bottom. */
064 public static final RectangleEdge BOTTOM
065 = new RectangleEdge("RectangleEdge.BOTTOM");
066
067 /** Left. */
068 public static final RectangleEdge LEFT
069 = new RectangleEdge("RectangleEdge.LEFT");
070
071 /** Right. */
072 public static final RectangleEdge RIGHT
073 = new RectangleEdge("RectangleEdge.RIGHT");
074
075 /** The name. */
076 private String name;
077
078 /**
079 * Private constructor.
080 *
081 * @param name the name.
082 */
083 private RectangleEdge(final String name) {
084 this.name = name;
085 }
086
087 /**
088 * Returns a string representing the object.
089 *
090 * @return The string.
091 */
092 public String toString() {
093 return this.name;
094 }
095
096 /**
097 * Returns <code>true</code> if this object is equal to the specified
098 * object, and <code>false</code> otherwise.
099 *
100 * @param o the other object.
101 *
102 * @return A boolean.
103 */
104 public boolean equals(final Object o) {
105
106 if (this == o) {
107 return true;
108 }
109 if (!(o instanceof RectangleEdge)) {
110 return false;
111 }
112
113 final RectangleEdge order = (RectangleEdge) o;
114 if (!this.name.equals(order.name)) {
115 return false;
116 }
117
118 return true;
119
120 }
121
122 /**
123 * Returns a hash code value for the object.
124 *
125 * @return the hashcode
126 */
127 public int hashCode() {
128 return this.name.hashCode();
129 }
130
131 /**
132 * Returns <code>true</code> if the edge is <code>TOP</code> or
133 * <code>BOTTOM</code>, and <code>false</code> otherwise.
134 *
135 * @param edge the edge.
136 *
137 * @return A boolean.
138 */
139 public static boolean isTopOrBottom(final RectangleEdge edge) {
140 return (edge == RectangleEdge.TOP || edge == RectangleEdge.BOTTOM);
141 }
142
143 /**
144 * Returns <code>true</code> if the edge is <code>LEFT</code> or
145 * <code>RIGHT</code>, and <code>false</code> otherwise.
146 *
147 * @param edge the edge.
148 *
149 * @return A boolean.
150 */
151 public static boolean isLeftOrRight(final RectangleEdge edge) {
152 return (edge == RectangleEdge.LEFT || edge == RectangleEdge.RIGHT);
153 }
154
155 /**
156 * Returns the opposite edge.
157 *
158 * @param edge an edge.
159 *
160 * @return The opposite edge.
161 */
162 public static RectangleEdge opposite(final RectangleEdge edge) {
163 RectangleEdge result = null;
164 if (edge == RectangleEdge.TOP) {
165 result = RectangleEdge.BOTTOM;
166 }
167 else if (edge == RectangleEdge.BOTTOM) {
168 result = RectangleEdge.TOP;
169 }
170 else if (edge == RectangleEdge.LEFT) {
171 result = RectangleEdge.RIGHT;
172 }
173 else if (edge == RectangleEdge.RIGHT) {
174 result = RectangleEdge.LEFT;
175 }
176 return result;
177 }
178
179 /**
180 * Returns the x or y coordinate of the specified edge.
181 *
182 * @param rectangle the rectangle.
183 * @param edge the edge.
184 *
185 * @return The coordinate.
186 */
187 public static double coordinate(final Rectangle2D rectangle,
188 final RectangleEdge edge) {
189 double result = 0.0;
190 if (edge == RectangleEdge.TOP) {
191 result = rectangle.getMinY();
192 }
193 else if (edge == RectangleEdge.BOTTOM) {
194 result = rectangle.getMaxY();
195 }
196 else if (edge == RectangleEdge.LEFT) {
197 result = rectangle.getMinX();
198 }
199 else if (edge == RectangleEdge.RIGHT) {
200 result = rectangle.getMaxX();
201 }
202 return result;
203 }
204
205 /**
206 * Ensures that serialization returns the unique instances.
207 *
208 * @return The object.
209 *
210 * @throws ObjectStreamException if there is a problem.
211 */
212 private Object readResolve() throws ObjectStreamException {
213 RectangleEdge result = null;
214 if (this.equals(RectangleEdge.TOP)) {
215 result = RectangleEdge.TOP;
216 }
217 else if (this.equals(RectangleEdge.BOTTOM)) {
218 result = RectangleEdge.BOTTOM;
219 }
220 else if (this.equals(RectangleEdge.LEFT)) {
221 result = RectangleEdge.LEFT;
222 }
223 else if (this.equals(RectangleEdge.RIGHT)) {
224 result = RectangleEdge.RIGHT;
225 }
226 return result;
227 }
228
229 }