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.math3.genetics;
018
019 import java.util.ArrayList;
020 import java.util.Arrays;
021 import java.util.Collections;
022 import java.util.List;
023
024 /**
025 * Chromosome represented by an immutable list of a fixed length.
026 *
027 * @param <T> type of the representation list
028 * @version $Id: AbstractListChromosome.java 1416643 2012-12-03 19:37:14Z tn $
029 * @since 2.0
030 */
031 public abstract class AbstractListChromosome<T> extends Chromosome {
032
033 /** List representing the chromosome */
034 private final List<T> representation;
035
036 /**
037 * Constructor.
038 * @param representation inner representation of the chromosome
039 * @throws InvalidRepresentationException iff the <code>representation</code> can not represent a valid chromosome
040 */
041 public AbstractListChromosome(final List<T> representation) throws InvalidRepresentationException {
042 checkValidity(representation);
043 this.representation = Collections.unmodifiableList(new ArrayList<T> (representation));
044 }
045
046 /**
047 * Constructor.
048 * @param representation inner representation of the chromosome
049 * @throws InvalidRepresentationException iff the <code>representation</code> can not represent a valid chromosome
050 */
051 public AbstractListChromosome(final T[] representation) throws InvalidRepresentationException {
052 this(Arrays.asList(representation));
053 }
054
055 /**
056 * Asserts that <code>representation</code> can represent a valid chromosome.
057 *
058 * @param chromosomeRepresentation representation of the chromosome
059 * @throws InvalidRepresentationException iff the <code>representation</code> can not represent a valid chromosome
060 */
061 protected abstract void checkValidity(List<T> chromosomeRepresentation) throws InvalidRepresentationException;
062
063 /**
064 * Returns the (immutable) inner representation of the chromosome.
065 * @return the representation of the chromosome
066 */
067 protected List<T> getRepresentation() {
068 return representation;
069 }
070
071 /**
072 * Returns the length of the chromosome.
073 * @return the length of the chromosome
074 */
075 public int getLength() {
076 return getRepresentation().size();
077 }
078
079 /**
080 * Creates a new instance of the same class as <code>this</code> is, with a given <code>arrayRepresentation</code>.
081 * This is needed in crossover and mutation operators, where we need a new instance of the same class, but with
082 * different array representation.
083 * <p>
084 * Usually, this method just calls a constructor of the class.
085 *
086 * @param chromosomeRepresentation the inner array representation of the new chromosome.
087 * @return new instance extended from FixedLengthChromosome with the given arrayRepresentation
088 */
089 public abstract AbstractListChromosome<T> newFixedLengthChromosome(final List<T> chromosomeRepresentation);
090
091 @Override
092 public String toString() {
093 return String.format("(f=%s %s)", getFitness(), getRepresentation());
094 }
095 }