HistogramBin.java

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2011, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
 * Other names may be trademarks of their respective owners.]
 *
 * -----------------
 * HistogramBin.java
 * -----------------
 * (C) Copyright 2003-2008, by Jelai Wang and Contributors.
 *
 * Original Author:  Jelai Wang (jelaiw AT mindspring.com);
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * Changes
 * -------
 * 06-Jul-2003 : Version 1, contributed by Jelai Wang (DG);
 * 07-Jul-2003 : Changed package and added Javadocs (DG);
 * 01-Mar-2004 : Moved from org.jfree.data --> org.jfree.data.statistics (DG);
 * ------------- JFREECHART 1.0.x ---------------------------------------------
 * 02-Feb-2007 : Removed author tags from all over JFreeChart sources (DG);
 *
 */

package org.jfree.data.statistics;

import java.io.Serializable;

/**
 * A bin for the {@link HistogramDataset} class.
 */
public class HistogramBin implements Cloneable, Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 7614685080015589931L;

    /** The number of items in the bin. */
    private int count;

    /** The start boundary. */
    private double startBoundary;

    /** The end boundary. */
    private double endBoundary;

    /**
     * Creates a new bin.
     *
     * @param startBoundary  the start boundary.
     * @param endBoundary  the end boundary.
     */
    public HistogramBin(double startBoundary, double endBoundary) {
        if (startBoundary > endBoundary) {
            throw new IllegalArgumentException(
                    "HistogramBin():  startBoundary > endBoundary.");
        }
        this.count = 0;
        this.startBoundary = startBoundary;
        this.endBoundary = endBoundary;
    }

    /**
     * Returns the number of items in the bin.
     *
     * @return The item count.
     */
    public int getCount() {
        return this.count;
    }

    /**
     * Increments the item count.
     */
    public void incrementCount() {
        this.count++;
    }

    /**
     * Returns the start boundary.
     *
     * @return The start boundary.
     */
    public double getStartBoundary() {
        return this.startBoundary;
    }

    /**
     * Returns the end boundary.
     *
     * @return The end boundary.
     */
    public double getEndBoundary() {
        return this.endBoundary;
    }

    /**
     * Returns the bin width.
     *
     * @return The bin width.
     */
    public double getBinWidth() {
        return this.endBoundary - this.startBoundary;
    }

    /**
     * Tests this object for equality with an arbitrary object.
     *
     * @param obj  the object to test against.
     *
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (obj == this) {
            return true;
        }
        if (obj instanceof HistogramBin) {
            HistogramBin bin = (HistogramBin) obj;
            boolean b0 = bin.startBoundary == this.startBoundary;
            boolean b1 = bin.endBoundary == this.endBoundary;
            boolean b2 = bin.count == this.count;
            return b0 && b1 && b2;
        }
        return false;
    }

    /**
     * Returns a clone of the bin.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException not thrown by this class.
     */
    public Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

}