jfreechart example source code file (HistogramType.java)

This example jfreechart source code file (HistogramType.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

frequency, frequency, histogramtype, histogramtype, io, object, objectstreamexception, relative_frequency, scale_area_to_1, scale_area_to_1, serializable, string, string

The jfreechart HistogramType.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, 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.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * ------------------
 * HistogramType.java
 * ------------------
 * (C) Copyright 2004-2008, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * Changes
 * -------
 * 05-Mar-2004 : Version 1 (DG);
 *
 */

package org.jfree.data.statistics;

import java.io.ObjectStreamException;
import java.io.Serializable;

/**
 * A class for creating constants to represent the histogram type.  See Bloch's
 * enum tip in 'Effective Java'.
 */
public class HistogramType implements Serializable {

    /** For serialization. */
    private static final long serialVersionUID = 2618927186251997727L;

    /** Frequency histogram. */
    public static final HistogramType FREQUENCY
        = new HistogramType("FREQUENCY");

    /** Relative frequency. */
    public static final HistogramType RELATIVE_FREQUENCY
        = new HistogramType("RELATIVE_FREQUENCY");

    /** Scale area to one. */
    public static final HistogramType SCALE_AREA_TO_1
        = new HistogramType("SCALE_AREA_TO_1");

    /** The type name. */
    private String name;

    /**
     * Creates a new type.
     *
     * @param name  the name.
     */
    private HistogramType(String name) {
        this.name = name;
    }

    /**
     * Returns a string representing the object.
     *
     * @return The string.
     */
    public String toString() {
        return this.name;
    }

    /**
     * Tests this type 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 HistogramType)) {
            return false;
        }

        HistogramType t = (HistogramType) obj;
        if (!this.name.equals(t.name)) {
            return false;
        }

        return true;

    }

    /**
     * Returns a hash code value for the object.
     *
     * @return The hashcode
     */
    public int hashCode() {
        return this.name.hashCode();
    }

    /**
     * Ensures that serialization returns the unique instances.
     *
     * @return The object.
     *
     * @throws ObjectStreamException if there is a problem.
     */
    private Object readResolve() throws ObjectStreamException {
        if (this.equals(HistogramType.FREQUENCY)) {
            return HistogramType.FREQUENCY;
        }
        else if (this.equals(HistogramType.RELATIVE_FREQUENCY)) {
            return HistogramType.RELATIVE_FREQUENCY;
        }
        else if (this.equals(HistogramType.SCALE_AREA_TO_1)) {
            return HistogramType.SCALE_AREA_TO_1;
        }
        return null;
    }

}