001/*
002 * Java Genetic Algorithm Library (jenetics-8.1.0).
003 * Copyright (c) 2007-2024 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@gmail.com)
019 */
020package io.jenetics;
021
022import static java.util.Objects.requireNonNull;
023import static io.jenetics.internal.util.SerialIO.readInt;
024import static io.jenetics.internal.util.SerialIO.writeInt;
025
026import java.io.DataInput;
027import java.io.DataOutput;
028import java.io.IOException;
029import java.io.InvalidObjectException;
030import java.io.ObjectInputStream;
031import java.io.Serial;
032import java.io.Serializable;
033import java.util.function.Function;
034import java.util.stream.IntStream;
035import java.util.stream.Stream;
036
037import io.jenetics.util.ISeq;
038import io.jenetics.util.IntRange;
039import io.jenetics.util.MSeq;
040
041/**
042 * Numeric chromosome implementation which holds 32-bit integer numbers.
043 *
044 * @see IntegerGene
045 *
046 * @implNote
047 * This class is immutable and thread-safe.
048 *
049 * @author <a href="mailto:franz.wilhelmstoetter@gmail.com">Franz  Wilhelmstötter</a>
050 * @since 2.0
051 * @version 7.0
052 */
053public class IntegerChromosome
054        extends AbstractBoundedChromosome<Integer, IntegerGene>
055        implements
056                NumericChromosome<Integer, IntegerGene>,
057                Serializable
058{
059        @Serial
060        private static final long serialVersionUID = 3L;
061
062        /**
063         * Create a new chromosome from the given {@code genes} and the allowed
064         * length range of the chromosome.
065         *
066         * @since 4.0
067         *
068         * @param genes the genes that form the chromosome.
069         * @param lengthRange the allowed length range of the chromosome
070         * @throws NullPointerException if one of the arguments is {@code null}.
071         * @throws IllegalArgumentException if the length of the gene sequence is
072         *         empty, doesn't match with the allowed length range, the minimum
073         *         or maximum of the range is smaller or equal zero, or the given
074         *         range size is zero.
075         */
076        protected IntegerChromosome(
077                final ISeq<IntegerGene> genes,
078                final IntRange lengthRange
079        ) {
080                super(genes, lengthRange);
081        }
082
083        @Override
084        public IntegerChromosome newInstance(final ISeq<IntegerGene> genes) {
085                return new IntegerChromosome(genes, lengthRange());
086        }
087
088        @Override
089        public IntegerChromosome newInstance() {
090                return of(_min, _max, lengthRange());
091        }
092
093        /**
094         * Maps the gene alleles of this chromosome, given as {@code int[]} array,
095         * by applying the given mapper function {@code f}. The mapped gene values
096         * are then wrapped into a newly created chromosome.
097         *
098         * {@snippet lang="java":
099         * final IntegerChromosome chromosome = null; // @replace substring='null' replacement="..."
100         * final IntegerChromosome halved = chromosome.map(Main::half);
101         *
102         * static int[] half(final int[] values) {
103         *     for (int i = 0; i < values.length; ++i) {
104         *         values[i] /= 2;
105         *     }
106         *     return values;
107         * }
108         * }
109         *
110         * @since 6.1
111         *
112         * @param f the mapper function
113         * @return a newly created chromosome with the mapped gene values
114         * @throws NullPointerException if the mapper function is {@code null}.
115         * @throws IllegalArgumentException if the length of the mapped
116         *         {@code int[]} array is empty or doesn't match with the allowed
117         *         length range
118         */
119        public IntegerChromosome map(final Function<? super int[], int[]> f) {
120                requireNonNull(f);
121
122                final var range = IntRange.of(_min, _max);
123                final var genes = IntStream.of(f.apply(toArray()))
124                        .mapToObj(v -> IntegerGene.of(v, range))
125                        .collect(ISeq.toISeq());
126
127                return newInstance(genes);
128        }
129
130        /**
131         * Returns a sequential stream of the alleles with this chromosome as its
132         * source.
133         *
134         * @since 4.3
135         *
136         * @return a sequential stream of alleles
137         */
138        public IntStream intStream() {
139                return IntStream.range(0, length()).map(this::intValue);
140        }
141
142        /**
143         * Returns an int array containing all the elements in this chromosome in
144         * a proper sequence.  If the chromosome fits in the specified array, it is
145         * returned therein. Otherwise, a new array is allocated with the length of
146         * this chromosome.
147         *
148         * @since 3.0
149         *
150         * @param array the array into which the elements of these chromosomes are
151         *        to be stored, if it is big enough; otherwise, a new array is
152         *        allocated for this purpose.
153         * @return an array containing the elements of this chromosome
154         * @throws NullPointerException if the given {@code array} is {@code null}
155         */
156        public int[] toArray(final int[] array) {
157                final int[] a = array.length >= length() ? array : new int[length()];
158                for (int i = length(); --i >= 0;) {
159                        a[i] = intValue(i);
160                }
161
162                return a;
163        }
164
165        /**
166         * Returns an int array containing all the elements in this chromosome in
167         * a proper sequence.
168         *
169         * @since 3.0
170         *
171         * @return an array containing the elements of this chromosome
172         */
173        public int[] toArray() {
174                return toArray(new int[length()]);
175        }
176
177
178        /* *************************************************************************
179         * Static factory methods.
180         * ************************************************************************/
181
182        /**
183         * Create a new {@code IntegerChromosome} with the given genes.
184         *
185         * @param genes the genes of the chromosome
186         * @return a new chromosome with the given genes
187         * @throws IllegalArgumentException if the length of the genes array is
188         *         empty or the given {@code genes} doesn't have the same range
189         */
190        public static IntegerChromosome of(final IntegerGene... genes) {
191                checkGeneRange(Stream.of(genes).map(IntegerGene::range));
192                return new IntegerChromosome(ISeq.of(genes), IntRange.of(genes.length));
193        }
194
195        /**
196         * Create a new {@code IntegerChromosome} with the given genes.
197         *
198         * @since 4.3
199         *
200         * @param genes the genes of the chromosome.
201         * @return a new chromosome with the given genes.
202         * @throws NullPointerException if the given {@code genes} are {@code null}
203         * @throws IllegalArgumentException if the of the genes iterable is empty or
204         *         the given {@code genes} doesn't have the same range.
205         */
206        public static IntegerChromosome of(final Iterable<IntegerGene> genes) {
207                final ISeq<IntegerGene> values = ISeq.of(genes);
208                checkGeneRange(values.stream().map(IntegerGene::range));
209                return new IntegerChromosome(values, IntRange.of(values.length()));
210        }
211
212        /**
213         * Create a new random chromosome.
214         *
215         * @since 4.0
216         *
217         * @param min the min value of the {@link IntegerGene}s (inclusively).
218         * @param max the max value of the {@link IntegerGene}s (exclusively).
219         * @param lengthRange the allowed length range of the chromosome.
220         * @return a new {@code IntegerChromosome} with the given parameter
221         * @throws IllegalArgumentException if the length of the gene sequence is
222         *         empty, doesn't match with the allowed length range, the minimum
223         *         or maximum of the range is smaller or equal zero, or the given
224         *         range size is zero.
225         * @throws IllegalArgumentException if {@code max} is greater than
226         *         or equal to {@code min}
227         * @throws NullPointerException if the given {@code lengthRange} is
228         *         {@code null}
229         */
230        public static IntegerChromosome of(
231                final int min,
232                final int max,
233                final IntRange lengthRange
234        ) {
235                final ISeq<IntegerGene> values = IntegerGene.seq(min, max, lengthRange);
236                return new IntegerChromosome(values, lengthRange);
237        }
238
239        /**
240         * Create a new random {@code IntegerChromosome}.
241         *
242         * @param min the min value of the {@link IntegerGene}s (inclusively).
243         * @param max the max value of the {@link IntegerGene}s (exclusively).
244         * @param length the length of the chromosome.
245         * @return a new random {@code IntegerChromosome}
246         * @throws IllegalArgumentException if the length is smaller than one
247         * @throws IllegalArgumentException if {@code max} is greater than
248         *         or equal to {@code min}
249         */
250        public static IntegerChromosome of(
251                final int min,
252                final int max,
253                final int length
254        ) {
255                return of(min, max, IntRange.of(length));
256        }
257
258        /**
259         * Create a new random chromosome.
260         *
261         * @since 4.0
262         *
263         * @param range the integer range of the chromosome.
264         * @param lengthRange the allowed length range of the chromosome.
265         * @return a new {@code IntegerChromosome} with the given parameter
266         * @throws IllegalArgumentException if the length of the gene sequence is
267         *         empty, doesn't match with the allowed length range, the minimum
268         *         or maximum of the range is smaller or equal zero, or the given
269         *         range size is zero.
270         * @throws NullPointerException if the given {@code lengthRange} is
271         *         {@code null}
272         * @throws IllegalArgumentException if {@code max} is greater than
273         *         or equal to {@code min}
274         */
275        public static IntegerChromosome of(
276                final IntRange range,
277                final IntRange lengthRange
278        ) {
279                return of(range.min(), range.max(), lengthRange);
280        }
281
282        /**
283         * Create a new random {@code IntegerChromosome}.
284         *
285         * @since 3.2
286         *
287         * @param range the integer range of the chromosome.
288         * @param length the length of the chromosome.
289         * @return a new random {@code IntegerChromosome}
290         * @throws NullPointerException if the given {@code range} is {@code null}
291         * @throws IllegalArgumentException if the length is smaller than one
292         * @throws IllegalArgumentException if {@code max} is greater than
293         *         or equal to {@code min}
294         */
295        public static IntegerChromosome of(final IntRange range, final int length) {
296                return of(range.min(), range.max(), length);
297        }
298
299        /**
300         * Create a new random {@code IntegerChromosome} of length one.
301         *
302         * @param min the minimal value of this chromosome (inclusively).
303         * @param max the maximal value of this chromosome (exclusively).
304         * @return a new random {@code IntegerChromosome} of length one
305         * @throws IllegalArgumentException if {@code max} is greater than
306         *         or equal to {@code min}
307         */
308        public static IntegerChromosome of(final int min, final int max) {
309                return of(min, max, 1);
310        }
311
312        /**
313         * Create a new random {@code IntegerChromosome} of length one.
314         *
315         * @since 3.2
316         *
317         * @param range the integer range of the chromosome.
318         * @return a new random {@code IntegerChromosome} of length one
319         * @throws NullPointerException if the given {@code range} is {@code null}
320         * @throws IllegalArgumentException if {@code max} is greater than
321         *         or equal to {@code min}
322         */
323        public static IntegerChromosome of(final IntRange range) {
324                return of(range.min(), range.max(), 1);
325        }
326
327
328
329        /* *************************************************************************
330         *  Java object serialization
331         * ************************************************************************/
332
333        @Serial
334        private Object writeReplace() {
335                return new SerialProxy(SerialProxy.INTEGER_CHROMOSOME, this);
336        }
337
338        @Serial
339        private void readObject(final ObjectInputStream stream)
340                throws InvalidObjectException
341        {
342                throw new InvalidObjectException("Serialization proxy required.");
343        }
344
345        void write(final DataOutput out) throws IOException {
346                writeInt(length(), out);
347                writeInt(lengthRange().min(), out);
348                writeInt(lengthRange().max(), out);
349                writeInt(_min, out);
350                writeInt(_max, out);
351
352                for (int i = 0, n = length(); i < n; ++i) {
353                        writeInt(intValue(i), out);
354                }
355        }
356
357        static IntegerChromosome read(final DataInput in) throws IOException {
358                final var length = readInt(in);
359                final var lengthRange = IntRange.of(readInt(in), readInt(in));
360                final var min = readInt(in);
361                final var max = readInt(in);
362
363                final MSeq<IntegerGene> values = MSeq.ofLength(length);
364                for (int i = 0; i < length; ++i) {
365                        values.set(i, IntegerGene.of(readInt(in), min, max));
366                }
367
368                return new IntegerChromosome(values.toISeq(), lengthRange);
369        }
370
371}