001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.math.genetics;
018    
019    import static org.junit.Assert.*;
020    
021    import org.junit.Test;
022    
023    public class ElitisticListPopulationTest {
024        
025        private static int counter = 0;
026    
027        @Test
028        public void testNextGeneration() {
029            ElitisticListPopulation pop = new ElitisticListPopulation(100, 0.203);
030            
031            for (int i=0; i<pop.getPopulationLimit(); i++) {
032                pop.addChromosome(new DummyChromosome());
033            }
034            
035            Population nextGeneration = pop.nextGeneration();
036            
037            assertEquals(20, nextGeneration.getPopulationSize());
038        }
039        
040        private static class DummyChromosome extends Chromosome {
041            private final int fitness;
042            
043            public DummyChromosome() {
044                this.fitness = counter;
045                counter++;
046            }
047            
048            public double fitness() {            
049                return this.fitness;
050            }
051        }
052    
053    }