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 * Layer.java
029 * ----------
030 * (C) Copyright 2003, 2004, by Object Refinery Limited.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: Layer.java,v 1.4 2005/10/18 13:18:34 mungady Exp $
036 *
037 * Changes:
038 * --------
039 * 17-Sep-2003 (DG);
040 *
041 */
042
043 package org.jfree.ui;
044
045 import java.io.ObjectStreamException;
046 import java.io.Serializable;
047
048 /**
049 * Used to indicate either the foreground or background layer.
050 *
051 * @author David Gilbert
052 */
053 public final class Layer implements Serializable {
054
055 /** For serialization. */
056 private static final long serialVersionUID = -1470104570733183430L;
057
058 /** Foreground. */
059 public static final Layer FOREGROUND = new Layer("Layer.FOREGROUND");
060
061 /** Background. */
062 public static final Layer BACKGROUND = new Layer("Layer.BACKGROUND");
063
064 /** The name. */
065 private String name;
066
067 /**
068 * Private constructor.
069 *
070 * @param name the name.
071 */
072 private Layer(final String name) {
073 this.name = name;
074 }
075
076 /**
077 * Returns a string representing the object.
078 *
079 * @return The string.
080 */
081 public String toString() {
082 return this.name;
083 }
084
085 /**
086 * Returns <code>true</code> if this object is equal to the specified
087 * object, and <code>false</code> otherwise.
088 *
089 * @param o the other object.
090 *
091 * @return A boolean.
092 */
093 public boolean equals(final Object o) {
094
095 if (this == o) {
096 return true;
097 }
098 if (!(o instanceof Layer)) {
099 return false;
100 }
101
102 final Layer layer = (Layer) o;
103 if (!this.name.equals(layer.name)) {
104 return false;
105 }
106
107 return true;
108
109 }
110
111 /**
112 * Returns a hash code value for the object.
113 *
114 * @return the hashcode
115 */
116 public int hashCode() {
117 return this.name.hashCode();
118 }
119
120 /**
121 * Ensures that serialization returns the unique instances.
122 *
123 * @return The object.
124 *
125 * @throws ObjectStreamException if there is a problem.
126 */
127 private Object readResolve() throws ObjectStreamException {
128 Layer result = null;
129 if (this.equals(Layer.FOREGROUND)) {
130 result = Layer.FOREGROUND;
131 }
132 else if (this.equals(Layer.BACKGROUND)) {
133 result = Layer.BACKGROUND;
134 }
135 return result;
136 }
137
138 }
139