001 /*
002 * Java Genetic Algorithm Library (jenetics-1.6.0).
003 * Copyright (c) 2007-2014 Franz Wilhelmstötter
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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 * Author:
018 * Franz Wilhelmstötter (franz.wilhelmstoetter@gmx.at)
019 */
020 package org.jenetics;
021
022 import static java.lang.String.format;
023 import static java.util.Objects.requireNonNull;
024 import static org.jenetics.internal.util.object.Verify;
025 import static org.jenetics.internal.util.object.eq;
026 import static org.jenetics.util.functions.Null;
027
028 import java.util.Iterator;
029 import java.util.RandomAccess;
030
031 import org.jenetics.internal.util.HashBuilder;
032 import org.jenetics.internal.util.cast;
033
034 import org.jenetics.util.Function;
035 import org.jenetics.util.ISeq;
036
037 /**
038 * The abstract base implementation of the Chromosome interface. The implementors
039 * of this class must assure that the protected member {@code _genes} is not
040 * {@code null} and the length of the {@code genes} > 0.
041 *
042 * @param <G> the gene type.
043 *
044 * @author <a href="mailto:franz.wilhelmstoetter@gmx.at">Franz Wilhelmstötter</a>
045 * @since 1.0
046 * @version 1.5 — <em>$Date: 2014-03-01 $</em>
047 */
048 public abstract class AbstractChromosome<G extends Gene<?, G>>
049 implements
050 Chromosome<G>,
051 RandomAccess
052 {
053 private static final long serialVersionUID = 1;
054
055 /**
056 * Array of genes which forms the chromosome. This array must
057 * be initialized by the derived classes.
058 */
059 protected transient ISeq<G> _genes = null;
060
061 /**
062 * Indicates whether this chromosome is valid or not. If the variable is
063 * {@code null} the validation state hasn't been calculated yet.
064 */
065 protected transient Boolean _valid = null;
066
067 /**
068 * Create a new {@code AbstractChromosome} from the given {@code genes}
069 * array. The genes array is not copied, but sealed, so changes to the given
070 * genes array doesn't effect the genes of this chromosome.
071 *
072 * @param genes the genes that form the chromosome.
073 * @throws NullPointerException if the given gene array is {@code null}.
074 * @throws IllegalArgumentException if the length of the gene array is
075 * smaller than one.
076 */
077 protected AbstractChromosome(final ISeq<? extends G> genes) {
078 requireNonNull(genes, "Gene array");
079 assert (genes.indexWhere(Null) == -1) : "Found at least on null gene.";
080
081 if (genes.length() < 1) {
082 throw new IllegalArgumentException(format(
083 "Chromosome length < 1: %d", genes.length()
084 ));
085 }
086
087 _genes = cast.apply(genes);
088 }
089
090 @Override
091 public G getGene(final int index) {
092 return _genes.get(index);
093 }
094
095 @Override
096 public G getGene() {
097 return _genes.get(0);
098 }
099
100 @Override
101 public ISeq<G> toSeq() {
102 return _genes;
103 }
104
105 @Override
106 public boolean isValid() {
107 if (_valid == null) {
108 _valid = _genes.forAll(Verify);
109 }
110
111 return _valid;
112 }
113
114 @Override
115 public Iterator<G> iterator() {
116 return _genes.iterator();
117 }
118
119 @Override
120 public int length() {
121 return _genes.length();
122 }
123
124 /**
125 * Return the index of the first occurrence of the given {@code gene}.
126 *
127 * @param gene the {@link Gene} to search for.
128 * @return the index of the searched gene, or -1 if the given gene was not
129 * found.
130 */
131 protected int indexOf(final Object gene) {
132 return _genes.indexOf(gene);
133 }
134
135 @Override
136 public int hashCode() {
137 return HashBuilder.of(getClass()).and(_genes).value();
138 }
139
140 @Override
141 public boolean equals(final Object obj) {
142 if (obj == this) {
143 return true;
144 }
145 if (obj == null || getClass() != obj.getClass()) {
146 return false;
147 }
148
149 final AbstractChromosome<?> chromosome = (AbstractChromosome<?>)obj;
150 return eq(_genes, chromosome._genes);
151 }
152
153 @Override
154 public String toString() {
155 return _genes.toString();
156 }
157
158
159 /* *************************************************************************
160 * Property access methods
161 * ************************************************************************/
162
163 /**
164 * Return a {@link Function} which returns the first {@link Gene} from this
165 * {@link Chromosome}.
166 */
167 static <G extends Gene<?, G>, C extends Chromosome<G>>
168 Function<C, G> gene() {
169 return new Function<C, G>() {
170 @Override public G apply(final C value) {
171 return value.getGene();
172 }
173 };
174 }
175
176 /**
177 * Return a {@link Function} which returns the {@link Gene} with the given
178 * {@code index} from this {@link Chromosome}.
179 */
180 static <G extends Gene<?, G>, C extends Chromosome<G>>
181 Function<C, G> gene(final int index) {
182 return new Function<C, G>() {
183 @Override public G apply(final C value) {
184 return value.getGene(index);
185 }
186 };
187 }
188
189 /**
190 * Return a {@link Function} which returns the gene array from this
191 * {@link Chromosome}.
192 */
193 static <G extends Gene<?, G>, C extends Chromosome<G>>
194 Function<C, ISeq<G>> genes() {
195 return new Function<C, ISeq<G>>() {
196 @Override public ISeq<G> apply(final C value) {
197 return value.toSeq();
198 }
199 };
200 }
201
202 }
|