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     * MeanAndStandardDeviation.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: MeanAndStandardDeviation.java,v 1.3.2.1 2005/10/25 21:34:46 mungady Exp $
036     *
037     * Changes:
038     * --------
039     * 05-Feb-2002 : Version 1 (DG);
040     * 05-Feb-2005 : Added equals() method and implemented Serializable (DG);
041     *
042     */
043    
044    package org.jfree.data.statistics;
045    
046    import java.io.Serializable;
047    
048    import org.jfree.util.ObjectUtilities;
049    
050    /**
051     * A simple data structure that holds a mean value and a standard deviation 
052     * value.  This is used in the 
053     * {@link org.jfree.data.statistics.DefaultStatisticalCategoryDataset} class.
054     */
055    public class MeanAndStandardDeviation implements Serializable {
056    
057        /** For serialization. */
058        private static final long serialVersionUID = 7413468697315721515L;
059        
060        /** The mean. */
061        private Number mean;
062    
063        /** The standard deviation. */
064        private Number standardDeviation;
065    
066        /**
067         * Creates a new mean and standard deviation record.
068         * 
069         * @param mean  the mean.
070         * @param standardDeviation  the standard deviation.
071         */
072        public MeanAndStandardDeviation(double mean, double standardDeviation) {
073            this(new Double(mean), new Double(standardDeviation));   
074        }
075        
076        /**
077         * Creates a new mean and standard deviation record.
078         *
079         * @param mean  the mean (<code>null</code> permitted).
080         * @param standardDeviation  the standard deviation (<code>null</code>
081         *                           permitted.
082         */
083        public MeanAndStandardDeviation(Number mean, Number standardDeviation) {
084            this.mean = mean;
085            this.standardDeviation = standardDeviation;
086        }
087    
088        /**
089         * Returns the mean.
090         *
091         * @return The mean.
092         */
093        public Number getMean() {
094            return this.mean;
095        }
096    
097        /**
098         * Returns the standard deviation.
099         *
100         * @return The standard deviation.
101         */
102        public Number getStandardDeviation() {
103            return this.standardDeviation;
104        }
105    
106        /**
107         * Tests this instance for equality with an arbitrary object.
108         * 
109         * @param obj  the object (<code>null</code> permitted).
110         * 
111         * @return A boolean.
112         */
113        public boolean equals(Object obj) {
114            if (obj == this) {
115                return true;   
116            }
117            if (!(obj instanceof MeanAndStandardDeviation)) {
118                return false;   
119            }
120            MeanAndStandardDeviation that = (MeanAndStandardDeviation) obj;
121            if (!ObjectUtilities.equal(this.mean, that.mean)) {
122                return false;   
123            }
124            if (!ObjectUtilities.equal(
125                this.standardDeviation, that.standardDeviation)
126            ) {
127                return false;   
128            }
129            return true;
130        }
131    }