jfreechart example source code file (LogarithmicAxisTests.java)

This example jfreechart source code file (LogarithmicAxisTests.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

awt, axis, center, epsilon, epsilon, exception, geometry, io, left, logarithmicaxis, logarithmicaxis, logarithmicaxistests, mylogarithmicaxis, mylogarithmicaxis, rectangle2d, rectangle2d, test

The jfreechart LogarithmicAxisTests.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.]
 *
 * -------------------------
 * LogarithmicAxisTests.java
 * -------------------------
 * (C) Copyright 2003-2008, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * Changes
 * -------
 * 26-Mar-2003 : Version 1 (DG);
 * 02-Mar-2007 : Added tests from bug report 880597 (DG);
 *
 */

package org.jfree.chart.axis.junit;

import java.awt.geom.Rectangle2D;
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.chart.axis.LogarithmicAxis;
import org.jfree.ui.RectangleEdge;

/**
 * Tests for the {@link LogarithmicAxis} class.
 */
public class LogarithmicAxisTests extends TestCase {

    static class MyLogarithmicAxis extends LogarithmicAxis {

        /**
         * Creates a new instance.
         *
         * @param label  the label.
         */
        public MyLogarithmicAxis(String label) {
            super(label);
        }

        /* (non-Javadoc)
         * @see org.jfree.chart.axis.LogarithmicAxis#switchedLog10(double)
         */
        protected double switchedLog10(double val) {
            return super.switchedLog10(val);
        }

    }

    /** Tolerance for floating point comparisons */
    public static double EPSILON = 0.000001;

    MyLogarithmicAxis axis = null;

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

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

    /**
     * Sets up a new axis.
     *
     * @throws Exception
     */
    protected void setUp() throws Exception {
        this.axis = new MyLogarithmicAxis("Value (log)");
        this.axis.setAllowNegativesFlag(false);
        this.axis.setLog10TickLabelsFlag(false);
        this.axis.setLowerMargin(0.0);
        this.axis.setUpperMargin(0.0);

        this.axis.setLowerBound(0.2);
        this.axis.setUpperBound(100.0);
    }

    /**
     * Serialize an instance, restore it, and check for equality.
     */
    public void testSerialization() {

        LogarithmicAxis a1 = new LogarithmicAxis("Test Axis");
        LogarithmicAxis a2 = null;

        try {
            ByteArrayOutputStream buffer = new ByteArrayOutputStream();
            ObjectOutput out = new ObjectOutputStream(buffer);
            out.writeObject(a1);
            out.close();

            ObjectInput in = new ObjectInputStream(new ByteArrayInputStream(
                    buffer.toByteArray()));
            a2 = (LogarithmicAxis) in.readObject();
            in.close();
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        assertEquals(a1, a2);

    }

    /**
     * Test if adjustedLog10 and adjustedPow10 are inverses of each other
     */
     public void testAdjustedLog10() {
         checkLogPowRoundTrip(20);
         checkLogPowRoundTrip(10);
         checkLogPowRoundTrip(5);
         checkLogPowRoundTrip(2);
         checkLogPowRoundTrip(1);
         checkLogPowRoundTrip(0.5);
         checkLogPowRoundTrip(0.2);
         checkLogPowRoundTrip(0.0001);
     }

     private void checkLogPowRoundTrip(double value) {
         assertEquals("log(pow(x)) = x", value, this.axis.adjustedLog10(
                 this.axis.adjustedPow10(value)), EPSILON);
         assertEquals("pow(log(x)) = x", value, this.axis.adjustedPow10(
                 this.axis.adjustedLog10(value)), EPSILON);
     }

     /**
      * Test if switchedLog10 and switchedPow10 are inverses of each other
      */
      public void testSwitchedLog10() {
          assertFalse("Axis should not allow negative values",
                  this.axis.getAllowNegativesFlag());

          assertEquals(Math.log(0.5) / LogarithmicAxis.LOG10_VALUE,
                  this.axis.switchedLog10(0.5), EPSILON);

          checkSwitchedLogPowRoundTrip(20);
          checkSwitchedLogPowRoundTrip(10);
          checkSwitchedLogPowRoundTrip(5);
          checkSwitchedLogPowRoundTrip(2);
          checkSwitchedLogPowRoundTrip(1);
          checkSwitchedLogPowRoundTrip(0.5);
          checkSwitchedLogPowRoundTrip(0.2);
          checkSwitchedLogPowRoundTrip(0.0001);
      }

      private void checkSwitchedLogPowRoundTrip(double value) {
          assertEquals("log(pow(x)) = x", value, this.axis.switchedLog10(
                  this.axis.switchedPow10(value)), EPSILON);
          assertEquals("pow(log(x)) = x", value, this.axis.switchedPow10(
                  this.axis.switchedLog10(value)), EPSILON);
      }

      /**
       * Test of java2DToValue method.
       */
      public void testJava2DToValue() {
          Rectangle2D plotArea = new Rectangle2D.Double(22, 33, 500, 500);
          RectangleEdge edge = RectangleEdge.BOTTOM;

          // set axis bounds to be both greater than 1
          this.axis.setRange(10, 20);
          checkPointsToValue(edge, plotArea);

          // check for bounds interval that includes 1
          this.axis.setRange(0.5, 10);
          checkPointsToValue(edge, plotArea);

          // check for bounds interval that includes 1
          this.axis.setRange(0.2, 20);
          checkPointsToValue(edge, plotArea);

          // check for both bounds smaller than 1
          this.axis.setRange(0.2, 0.7);
          checkPointsToValue(edge, plotArea);
      }

      /**
       * Test of valueToJava2D method.
       */
      public void testValueToJava2D() {
          Rectangle2D plotArea = new Rectangle2D.Double(22, 33, 500, 500);
          RectangleEdge edge = RectangleEdge.BOTTOM;

          // set axis bounds to be both greater than 1
          this.axis.setRange(10, 20);
          checkPointsToJava2D(edge, plotArea);

          // check for bounds interval that includes 1
          this.axis.setRange(0.5, 10);
          checkPointsToJava2D(edge, plotArea);

          // check for bounds interval that includes 1
          this.axis.setRange(0.2, 20);
          checkPointsToJava2D(edge, plotArea);

          // check for both bounds smaller than 1
          this.axis.setRange(0.2, 0.7);
          checkPointsToJava2D(edge, plotArea);
      }

      private void checkPointsToJava2D(RectangleEdge edge,
              Rectangle2D plotArea) {
          assertEquals("Left most point on the axis should be beginning of "
                  + "range.", plotArea.getX(), this.axis.valueToJava2D(
                  this.axis.getLowerBound(), plotArea, edge), EPSILON);
          assertEquals("Right most point on the axis should be end of range.",
                  plotArea.getX() + plotArea.getWidth(),
                  this.axis.valueToJava2D(this.axis.getUpperBound(),
                  plotArea, edge), EPSILON);
          assertEquals("Center point on the axis should geometric mean of the bounds.",
                  plotArea.getX() + (plotArea.getWidth() / 2),
                  this.axis.valueToJava2D(Math.sqrt(this.axis.getLowerBound()
                  * this.axis.getUpperBound()), plotArea, edge), EPSILON);
        }

    /**
     * Check the translation java2D to value for left, right, and center point.
     *
     * @param edge  the edge.
     * @param plotArea  the plot area.
     */
     private void checkPointsToValue(RectangleEdge edge, Rectangle2D plotArea) {
         assertEquals("Right most point on the axis should be end of range.",
                 this.axis.getUpperBound(), this.axis.java2DToValue(
                 plotArea.getX() + plotArea.getWidth(), plotArea, edge),
                 EPSILON);

         assertEquals("Left most point on the axis should be beginning of "
                 + "range.", this.axis.getLowerBound(),
                 this.axis.java2DToValue(plotArea.getX(), plotArea, edge),
                 EPSILON);

         assertEquals("Center point on the axis should geometric mean of the "
                 + "bounds.", Math.sqrt(this.axis.getUpperBound()
                 * this.axis.getLowerBound()), this.axis.java2DToValue(
                 plotArea.getX() + (plotArea.getWidth() / 2), plotArea, edge),
                 EPSILON);
    }

    /**
     * Runs all tests in this class.
     *
     * @param args  ignored.
     */
    public static void main(String[] args) {
        junit.textui.TestRunner.run(LogarithmicAxisTests.class);
    }

}