jfreechart example source code file (HistogramDatasetTests.java)

This example jfreechart source code file (HistogramDatasetTests.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

bytearrayoutputstream, clonenotsupportedexception, epsilon, epsilon, histogramdataset, histogramdataset, histogramdatasettests, io, objectinput, s1, s1, series, series, test, testcase

The jfreechart HistogramDatasetTests.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.]
 *
 * --------------------------
 * HistogramDatasetTests.java
 * --------------------------
 * (C) Copyright 2004-2008, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * Changes
 * -------
 * 01-Mar-2004 : Version 1 (DG);
 * 08-Jun-2005 : Added test for getSeriesKey(int) bug (DG);
 * 03-Aug-2006 : Added testAddSeries() and testBinBoundaries() method (DG);
 * 22-May-2008 : Added testAddSeries2() and enhanced testCloning() (DG);
 *
 */

package org.jfree.data.statistics.junit;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInput;
import java.io.ObjectInputStream;
import java.io.ObjectOutput;
import java.io.ObjectOutputStream;

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

import org.jfree.data.statistics.HistogramDataset;

/**
 * Tests for the {@link HistogramDataset} class.
 */
public class HistogramDatasetTests extends TestCase {

    /**
     * Returns the tests as a test suite.
     *
     * @return The test suite.
     */
    public static Test suite() {
        return new TestSuite(HistogramDatasetTests.class);
    }

    /**
     * Constructs a new set of tests.
     *
     * @param name  the name of the tests.
     */
    public HistogramDatasetTests(String name) {
        super(name);
    }

    private static final double EPSILON = 0.0000000001;

    /**
     * Some checks that the correct values are assigned to bins.
     */
    public void testBins() {
        double[] values = {1.0, 2.0, 3.0, 4.0, 6.0, 12.0, 5.0, 6.3, 4.5};
        HistogramDataset hd = new HistogramDataset();
        hd.addSeries("Series 1", values, 5);
        assertEquals(hd.getYValue(0, 0), 3.0, EPSILON);
        assertEquals(hd.getYValue(0, 1), 3.0, EPSILON);
        assertEquals(hd.getYValue(0, 2), 2.0, EPSILON);
        assertEquals(hd.getYValue(0, 3), 0.0, EPSILON);
        assertEquals(hd.getYValue(0, 4), 1.0, EPSILON);
    }

    /**
     * Confirm that the equals method can distinguish all the required fields.
     */
    public void testEquals() {
        double[] values = {1.0, 2.0, 3.0, 4.0, 6.0, 12.0, 5.0, 6.3, 4.5};
        HistogramDataset d1 = new HistogramDataset();
        d1.addSeries("Series 1", values, 5);
        HistogramDataset d2 = new HistogramDataset();
        d2.addSeries("Series 1", values, 5);

        assertTrue(d1.equals(d2));
        assertTrue(d2.equals(d1));

        d1.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertFalse(d1.equals(d2));
        d2.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertTrue(d1.equals(d2));
    }

    /**
     * Confirm that cloning works.
     */
    public void testCloning() {
        double[] values = {1.0, 2.0, 3.0, 4.0, 6.0, 12.0, 5.0, 6.3, 4.5};
        HistogramDataset d1 = new HistogramDataset();
        d1.addSeries("Series 1", values, 5);
        HistogramDataset d2 = null;
        try {
            d2 = (HistogramDataset) d1.clone();
        }
        catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
        assertTrue(d1 != d2);
        assertTrue(d1.getClass() == d2.getClass());
        assertTrue(d1.equals(d2));

        // simple check for independence
        d1.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertFalse(d1.equals(d2));
        d2.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertTrue(d1.equals(d2));
    }

    /**
     * Serialize an instance, restore it, and check for equality.
     */
    public void testSerialization() {
        double[] values = {1.0, 2.0, 3.0, 4.0, 6.0, 12.0, 5.0, 6.3, 4.5};
        HistogramDataset d1 = new HistogramDataset();
        d1.addSeries("Series 1", values, 5);
        HistogramDataset d2 = null;

        try {
            ByteArrayOutputStream buffer = new ByteArrayOutputStream();
            ObjectOutput out = new ObjectOutputStream(buffer);
            out.writeObject(d1);
            out.close();

            ObjectInput in = new ObjectInputStream(
                    new ByteArrayInputStream(buffer.toByteArray()));
            d2 = (HistogramDataset) in.readObject();
            in.close();
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        assertEquals(d1, d2);

        // simple check for independence
        d1.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertFalse(d1.equals(d2));
        d2.addSeries("Series 2", new double[] {1.0, 2.0, 3.0}, 2);
        assertTrue(d1.equals(d2));
    }

    /**
     * A test for a bug reported in the forum where the series name isn't being
     * returned correctly.
     */
    public void testGetSeriesKey() {
        double[] values = {1.0, 2.0, 3.0, 4.0, 6.0, 12.0, 5.0, 6.3, 4.5};
        HistogramDataset d1 = new HistogramDataset();
        d1.addSeries("Series 1", values, 5);
        assertEquals("Series 1", d1.getSeriesKey(0));
    }

    /**
     * Some checks for the addSeries() method.
     */
    public void testAddSeries() {
        double[] values = {-1.0, 0.0, 0.1, 0.9, 1.0, 1.1, 1.9, 2.0, 3.0};
        HistogramDataset d = new HistogramDataset();
        d.addSeries("S1", values, 2, 0.0, 2.0);
        assertEquals(0.0, d.getStartXValue(0, 0), EPSILON);
        assertEquals(1.0, d.getEndXValue(0, 0), EPSILON);
        assertEquals(4.0, d.getYValue(0, 0), EPSILON);

        assertEquals(1.0, d.getStartXValue(0, 1), EPSILON);
        assertEquals(2.0, d.getEndXValue(0, 1), EPSILON);
        assertEquals(5.0, d.getYValue(0, 1), EPSILON);
    }

    /**
     * Another check for the addSeries() method.
     */
    public void testAddSeries2() {
        double[] values = {0.0, 1.0, 2.0, 3.0, 4.0, 5.0};
        HistogramDataset hd = new HistogramDataset();
        hd.addSeries("S1", values, 5);
        assertEquals(0.0, hd.getStartXValue(0, 0), EPSILON);
        assertEquals(1.0, hd.getEndXValue(0, 0), EPSILON);
        assertEquals(1.0, hd.getYValue(0, 0), EPSILON);
        assertEquals(1.0, hd.getStartXValue(0, 1), EPSILON);
        assertEquals(2.0, hd.getEndXValue(0, 1), EPSILON);
        assertEquals(1.0, hd.getYValue(0, 1), EPSILON);
        assertEquals(2.0, hd.getStartXValue(0, 2), EPSILON);
        assertEquals(3.0, hd.getEndXValue(0, 2), EPSILON);
        assertEquals(1.0, hd.getYValue(0, 2), EPSILON);
        assertEquals(3.0, hd.getStartXValue(0, 3), EPSILON);
        assertEquals(4.0, hd.getEndXValue(0, 3), EPSILON);
        assertEquals(1.0, hd.getYValue(0, 3), EPSILON);
        assertEquals(4.0, hd.getStartXValue(0, 4), EPSILON);
        assertEquals(5.0, hd.getEndXValue(0, 4), EPSILON);
        assertEquals(2.0, hd.getYValue(0, 4), EPSILON);
    }

    /**
     * This test is derived from a reported bug.
     */
    public void testBinBoundaries() {
        double[] values = {-5.000000000000286E-5};
        int bins = 1260;
        double minimum = -0.06307522528160199;
        double maximum = 0.06297522528160199;
        HistogramDataset d = new HistogramDataset();
        d.addSeries("S1", values, bins, minimum, maximum);
        assertEquals(0.0, d.getYValue(0, 629), EPSILON);
        assertEquals(1.0, d.getYValue(0, 630), EPSILON);
        assertEquals(0.0, d.getYValue(0, 631), EPSILON);
        assertTrue(values[0] > d.getStartXValue(0, 630));
        assertTrue(values[0] < d.getEndXValue(0, 630));
    }

    /**
     * Some checks for bug 1553088.  An IndexOutOfBoundsException is thrown
     * when a data value is *very* close to the upper limit of the last bin.
     */
    public void test1553088() {
        double[] values = {-1.0, 0.0, -Double.MIN_VALUE, 3.0};
        HistogramDataset d = new HistogramDataset();
        d.addSeries("S1", values, 2, -1.0, 0.0);
        assertEquals(-1.0, d.getStartXValue(0, 0), EPSILON);
        assertEquals(-0.5, d.getEndXValue(0, 0), EPSILON);
        assertEquals(1.0, d.getYValue(0, 0), EPSILON);

        assertEquals(-0.5, d.getStartXValue(0, 1), EPSILON);
        assertEquals(0.0, d.getEndXValue(0, 1), EPSILON);
        assertEquals(3.0, d.getYValue(0, 1), EPSILON);
    }

}