/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.math3.random;
import java.util.Random;
/**
* Extension of <code>java.util.Random</code> wrapping a
* {@link RandomGenerator}.
*
* @since 1.1
*/
public class RandomAdaptor extends Random implements RandomGenerator {
/** Serializable version identifier. */
private static final long serialVersionUID = 2306581345647615033L;
/** Wrapped randomGenerator instance */
private final RandomGenerator randomGenerator;
/**
* Prevent instantiation without a generator argument
*/
@SuppressWarnings("unused")
private RandomAdaptor() { randomGenerator = null; }
/**
* Construct a RandomAdaptor wrapping the supplied RandomGenerator.
*
* @param randomGenerator the wrapped generator
*/
public RandomAdaptor(RandomGenerator randomGenerator) {
this.randomGenerator = randomGenerator;
}
/**
* Factory method to create a <code>Random</code> using the supplied
* <code>RandomGenerator</code>.
*
* @param randomGenerator wrapped RandomGenerator instance
* @return a Random instance wrapping the RandomGenerator
*/
public static Random createAdaptor(RandomGenerator randomGenerator) {
return new RandomAdaptor(randomGenerator);
}
/**
* Returns the next pseudorandom, uniformly distributed
* <code>boolean</code> value from this random number generator's
* sequence.
*
* @return the next pseudorandom, uniformly distributed
* <code>boolean</code> value from this random number generator's
* sequence
*/
@Override
public boolean nextBoolean() {
return randomGenerator.nextBoolean();
}
/**
* Generates random bytes and places them into a user-supplied
* byte array. The number of random bytes produced is equal to
* the length of the byte array.
*
* @param bytes the non-null byte array in which to put the
* random bytes
*/
@Override
public void nextBytes(byte[] bytes) {
randomGenerator.nextBytes(bytes);
}
/**
* Returns the next pseudorandom, uniformly distributed
* <code>double</code> value between <code>0.0</code> and
* <code>1.0</code> from this random number generator's sequence.
*
* @return the next pseudorandom, uniformly distributed
* <code>double</code> value between <code>0.0</code> and
* <code>1.0</code> from this random number generator's sequence
*/
@Override
public double nextDouble() {
return randomGenerator.nextDouble();
}
/**
* Returns the next pseudorandom, uniformly distributed <code>float</code>
* value between <code>0.0</code> and <code>1.0</code> from this random
* number generator's sequence.
*
* @return the next pseudorandom, uniformly distributed <code>float</code>
* value between <code>0.0</code> and <code>1.0</code> from this
* random number generator's sequence
*/
@Override
public float nextFloat() {
return randomGenerator.nextFloat();
}
/**
* Returns the next pseudorandom, Gaussian ("normally") distributed
* <code>double</code> value with mean <code>0.0</code> and standard
* deviation <code>1.0</code> from this random number generator's sequence.
*
* @return the next pseudorandom, Gaussian ("normally") distributed
* <code>double</code> value with mean <code>0.0</code> and
* standard deviation <code>1.0</code> from this random number
* generator's sequence
*/
@Override
public double nextGaussian() {
return randomGenerator.nextGaussian();
}
/**
* Returns the next pseudorandom, uniformly distributed <code>int</code>
* value from this random number generator's sequence.
* All 2<font size="-1"><sup>32</sup></font> possible {@code int} values
* should be produced with (approximately) equal probability.
*
* @return the next pseudorandom, uniformly distributed <code>int</code>
* value from this random number generator's sequence
*/
@Override
public int nextInt() {
return randomGenerator.nextInt();
}
/**
* Returns a pseudorandom, uniformly distributed {@code int} value
* between 0 (inclusive) and the specified value (exclusive), drawn from
* this random number generator's sequence.
*
* @param n the bound on the random number to be returned. Must be
* positive.
* @return a pseudorandom, uniformly distributed {@code int}
* value between 0 (inclusive) and n (exclusive).
* @throws IllegalArgumentException if n is not positive.
*/
@Override
public int nextInt(int n) {
return randomGenerator.nextInt(n);
}
/**
* Returns the next pseudorandom, uniformly distributed <code>long</code>
* value from this random number generator's sequence. All
* 2<font size="-1"><sup>64</sup></font> possible {@code long} values
* should be produced with (approximately) equal probability.
*
* @return the next pseudorandom, uniformly distributed <code>long</code>
*value from this random number generator's sequence
*/
@Override
public long nextLong() {
return randomGenerator.nextLong();
}
/** {@inheritDoc} */
public void setSeed(int seed) {
if (randomGenerator != null) { // required to avoid NPE in constructor
randomGenerator.setSeed(seed);
}
}
/** {@inheritDoc} */
public void setSeed(int[] seed) {
if (randomGenerator != null) { // required to avoid NPE in constructor
randomGenerator.setSeed(seed);
}
}
/** {@inheritDoc} */
@Override
public void setSeed(long seed) {
if (randomGenerator != null) { // required to avoid NPE in constructor
randomGenerator.setSeed(seed);
}
}
}