FitnessFunctionTest.java

/*
 * This file is part of JGAP.
 *
 * JGAP offers a dual license model containing the LGPL as well as the MPL.
 *
 * For licensing information please see the file license.txt included with JGAP
 * or have a look at the top of class org.jgap.Chromosome which representatively
 * includes the JGAP license policy applicable for any file delivered with JGAP.
 */
package org.jgap;

import junit.framework.*;

/**
 * Tests the FitnessFunction class.
 *
 * @author Klaus Meffert
 * @since 1.1
 */
public class FitnessFunctionTest
    extends JGAPTestCase {
  /** String containing the CVS revision. Read out via reflection!*/
  private final static String CVS_REVISION = "$Revision: 1.16 $";

  public static Test suite() {
    TestSuite suite = new TestSuite(FitnessFunctionTest.class);
    return suite;
  }

  public void testGetFitnessValue_0() {
    FitnessFunctionImpl fitfunc = new FitnessFunctionImpl(7);
    assertEquals(7.0d, fitfunc.getFitnessValue(null), 0.00000001d);
  }

  public void testGetFitnessValue_1() {
    try {
      FitnessFunctionImpl fitfunc = new FitnessFunctionImpl( -7);
      fitfunc.getFitnessValue(null);
      fail();
    }
    catch (RuntimeException cause) {
      ; // This is expected since non-positive fitness values are illegal.
    }
  }

  public void testGetFitnessValue_2() {
    try {
      FitnessFunctionImpl fitfunc = new FitnessFunctionImpl(0);
      fitfunc.getFitnessValue(null);
    }
    catch (RuntimeException cause) {
      ; // This is expected since non-positive fitness values are illegal.
    }
  }

  /**
   * @throws Exception
   *
   * @author Klaus Meffert
   * @since 2.6
   */
  public void testLastComputedValue_0()
      throws Exception {
    FitnessFunctionImpl fitfunc = new FitnessFunctionImpl(47.15d);
    assertEquals(FitnessFunction.NO_FITNESS_VALUE,
                 fitfunc.getLastComputedFitnessValue(), DELTA);
    IChromosome chrom = new Chromosome(new ConfigurationForTesting());
    fitfunc.getFitnessValue(chrom);
    assertEquals(47.15d, fitfunc.getLastComputedFitnessValue(), DELTA);
  }

  /**
   * Implementing class of abstract FitnessFunction class.
   *
   * @author Klaus Meffert
   * @since 1.1
   */
  private class FitnessFunctionImpl
      extends FitnessFunction {
    /**
     * @since 2.0 (until 1.1: type int)
     */
    private double m_evaluationValue;

    public FitnessFunctionImpl(double a_evaluationValue) {
      m_evaluationValue = a_evaluationValue;
    }

    protected double evaluate(IChromosome a_subject) {
      return m_evaluationValue;
    }
  }
}