001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2007, 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     * HistogramBin.java
029     * -----------------
030     * (C) Copyright 2003-2007, by Jelai Wang and Contributors.
031     *
032     * Original Author:  Jelai Wang (jelaiw AT mindspring.com);
033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
034     *
035     * $Id: HistogramBin.java,v 1.4.2.3 2007/02/02 15:50:24 mungady Exp $
036     *
037     * Changes
038     * -------
039     * 06-Jul-2003 : Version 1, contributed by Jelai Wang (DG);
040     * 07-Jul-2003 : Changed package and added Javadocs (DG);
041     * 01-Mar-2004 : Moved from org.jfree.data --> org.jfree.data.statistics (DG);
042     * ------------- JFREECHART 1.0.x ---------------------------------------------
043     * 02-Feb-2007 : Removed author tags from all over JFreeChart sources (DG);
044     * 
045     */
046    
047    package org.jfree.data.statistics;
048    
049    import java.io.Serializable;
050    
051    /**
052     * A bin for the {@link HistogramDataset} class.
053     */
054    public class HistogramBin implements Cloneable, Serializable {
055        
056        /** For serialization. */
057        private static final long serialVersionUID = 7614685080015589931L;
058        
059        /** The number of items in the bin. */
060        private int count;
061        
062        /** The start boundary. */
063        private double startBoundary;
064        
065        /** The end boundary. */
066        private double endBoundary;
067    
068        /**
069         * Creates a new bin.
070         * 
071         * @param startBoundary  the start boundary.
072         * @param endBoundary  the end boundary.
073         */
074        public HistogramBin(double startBoundary, double endBoundary) {
075            if (startBoundary > endBoundary) {
076                throw new IllegalArgumentException(
077                        "HistogramBin():  startBoundary > endBoundary.");
078            }
079            this.count = 0;
080            this.startBoundary = startBoundary;
081            this.endBoundary = endBoundary;
082        }
083    
084        /**
085         * Returns the number of items in the bin.
086         * 
087         * @return The item count.
088         */
089        public int getCount() {
090            return this.count;
091        }
092        
093        /**
094         * Increments the item count.
095         */
096        public void incrementCount() {
097            this.count++;
098        }
099        
100        /**
101         * Returns the start boundary.
102         * 
103         * @return The start boundary.
104         */
105        public double getStartBoundary() {
106            return this.startBoundary;
107        }
108        
109        /**
110         * Returns the end boundary.
111         * 
112         * @return The end boundary.
113         */
114        public double getEndBoundary() {
115            return this.endBoundary;
116        }
117        
118        /**
119         * Returns the bin width.
120         * 
121         * @return The bin width.
122         */
123        public double getBinWidth() {
124            return this.endBoundary - this.startBoundary;
125        }
126        
127        /**
128         * Tests this object for equality with an arbitrary object.
129         * 
130         * @param obj  the object to test against.
131         * 
132         * @return A boolean.
133         */
134        public boolean equals(Object obj) {
135            if (obj == null) {
136                return false;   
137            }
138            if (obj == this) {
139                return true;   
140            }
141            if (obj instanceof HistogramBin) {
142                HistogramBin bin = (HistogramBin) obj;
143                boolean b0 = bin.startBoundary == this.startBoundary;
144                boolean b1 = bin.endBoundary == this.endBoundary;
145                boolean b2 = bin.count == this.count;
146                return b0 && b1 && b2;
147            }
148            return false;
149        }
150        
151        /**
152         * Returns a clone of the bin.
153         * 
154         * @return A clone.
155         * 
156         * @throws CloneNotSupportedException not thrown by this class.
157         */
158        public Object clone() throws CloneNotSupportedException {
159            return super.clone();   
160        }
161        
162    }