001    package org.jaga.selection;
002    
003    
004    import java.util.Comparator;
005    import org.jaga.definitions.*;
006    
007    /**
008     * TODO: Complete these comments.
009     *
010     * <p><u>Project:</u> JAGA - Java API for Genetic Algorithms.</p>
011     *
012     * <p><u>Company:</u> University College London and JAGA.Org
013     *    (<a href="http://www.jaga.org" target="_blank">http://www.jaga.org</a>).
014     * </p>
015     *
016     * <p><u>Copyright:</u> (c) 2004 by G. Paperin.<br/>
017     *    This program is free software; you can redistribute it and/or modify
018     *    it under the terms of the GNU General Public License as published by
019     *    the Free Software Foundation, ONLY if you include a note of the original
020     *    author(s) in any redistributed/modified copy.<br/>
021     *    This program is distributed in the hope that it will be useful,
022     *    but WITHOUT ANY WARRANTY; without even the implied warranty of
023     *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
024     *    GNU General Public License for more details.<br/>
025     *    You should have received a copy of the GNU General Public License
026     *    along with this program; if not, write to the Free Software
027     *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
028     *    or see http://www.gnu.org/licenses/gpl.html</p>
029     *
030     * @author Greg Paperin (greg@jaga.org)
031     *
032     * @version JAGA public release 1.0 beta
033     */
034    
035    public class AbsoluteFitnessIndividualComparator implements Comparator {
036    
037            public AbsoluteFitnessIndividualComparator() {
038            }
039    
040            public int compare(Object o1, Object o2) {
041                    Individual ind1 = (Individual) o1;
042                    Individual ind2 = (Individual) o2;
043                    AbsoluteFitness fit1 = (AbsoluteFitness) ind1.getFitness();
044                    AbsoluteFitness fit2 = (AbsoluteFitness) ind2.getFitness();
045    
046                    double diff = fit1.getValue() - fit2.getValue();
047    
048                    if (-1 < diff && diff < 0)
049                            diff = -1;
050                    if (0 < diff && diff < 1)
051                            diff = 1;
052                    return (int) diff;
053            }
054    
055            public boolean equals(Object obj) {
056                    return this.equals(obj);
057            }
058    
059    }