/**
* Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
* contributors
*
* This file is part of EvoSuite.
*
* EvoSuite 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 3.0 of the License, or
* (at your option) any later version.
*
* EvoSuite 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 Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
*/
package org.evosuite.ga.comparators;
import java.io.Serializable;
import java.util.Comparator;
import org.evosuite.ga.Chromosome;
/**
* Sort a Collection of Chromosomes by Crowd
*
* @author José Campos
*/
public class CrowdingComparator
implements Comparator<Chromosome>, Serializable
{
/**
*
*/
private static final long serialVersionUID = -6576898111709166470L;
private boolean isToMaximize;
public CrowdingComparator(boolean maximize) {
this.isToMaximize = maximize;
}
@Override
public int compare(Chromosome c1, Chromosome c2)
{
if (c1.getRank() == c2.getRank() && c1.getDistance() == c2.getDistance())
return 0;
if (this.isToMaximize) {
if (c1.getRank() < c2.getRank())
return 1;
else if (c1.getRank() > c2.getRank())
return -1;
else if (c1.getRank() == c2.getRank())
return (c1.getDistance() > c2.getDistance()) ? -1 : 1;
}
else {
if (c1.getRank() < c2.getRank())
return -1;
else if (c1.getRank() > c2.getRank())
return 1;
else if (c1.getRank() == c2.getRank())
return (c1.getDistance() > c2.getDistance()) ? -1 : 1;
}
return 0;
}
}