001    /* ===========================================================
002     * JFreeChart : a free chart 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/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     * KeyedObject.java
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: KeyedObject.java,v 1.5.2.1 2005/10/25 21:29:13 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 05-Feb-2003 : Version 1 (DG);
040     * 27-Jan-2003 : Implemented Cloneable and Serializable, and added an equals()
041     *               method (DG);
042     *
043     */
044    
045    package org.jfree.data;
046    
047    import java.io.Serializable;
048    
049    import org.jfree.util.ObjectUtilities;
050    import org.jfree.util.PublicCloneable;
051    
052    /**
053     * A (key, object) pair.
054     */
055    public class KeyedObject implements Cloneable, PublicCloneable, Serializable {
056    
057        /** For serialization. */
058        private static final long serialVersionUID = 2677930479256885863L;
059        
060        /** The key. */
061        private Comparable key;
062    
063        /** The object. */
064        private Object object;
065    
066        /**
067         * Creates a new (key, object) pair.
068         *
069         * @param key  the key.
070         * @param object  the object (<code>null</code> permitted).
071         */
072        public KeyedObject(Comparable key, Object object) {
073            this.key = key;
074            this.object = object;
075        }
076    
077        /**
078         * Returns the key.
079         *
080         * @return The key.
081         */
082        public Comparable getKey() {
083            return this.key;
084        }
085    
086        /**
087         * Returns the object.
088         *
089         * @return The object (possibly <code>null</code>).
090         */
091        public Object getObject() {
092            return this.object;
093        }
094    
095        /**
096         * Sets the object.
097         *
098         * @param object  the object (<code>null</code> permitted).
099         */
100        public void setObject(Object object) {
101            this.object = object;
102        }
103        
104        /**
105         * Returns a clone of this object.  It is assumed that the key is an 
106         * immutable object, so it is not deep-cloned.  The object is deep-cloned 
107         * if it implements {@link PublicCloneable}, otherwise a shallow clone is 
108         * made.
109         * 
110         * @return A clone.
111         * 
112         * @throws CloneNotSupportedException if there is a problem cloning.
113         */
114        public Object clone() throws CloneNotSupportedException {
115            KeyedObject clone = (KeyedObject) super.clone();
116            if (this.object instanceof PublicCloneable) {
117                PublicCloneable pc = (PublicCloneable) this.object;
118                clone.object = pc.clone();
119            }
120            return clone;      
121        }
122        
123        /**
124         * Tests if this object is equal to another.
125         *
126         * @param obj  the other object.
127         *
128         * @return A boolean.
129         */
130        public boolean equals(Object obj) {
131    
132            if (obj == this) {
133                return true;
134            }
135    
136            if (!(obj instanceof KeyedObject)) {
137                return false;
138            }
139            KeyedObject that = (KeyedObject) obj;
140            if (!ObjectUtilities.equal(this.key, that.key)) {
141                return false;
142            }
143    
144            if (!ObjectUtilities.equal(this.object, that.object)) {
145                return false;
146            }
147    
148            return true;
149        }
150        
151    }