/*
* 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.caudexorigo.lang.math;
import java.util.Random;
/**
* <p>
* <code>RandomUtils</code> is a wrapper that supports all possible {@link java.util.Random} methods via the {@link java.lang.Math#random()} method and its system-wide <code>Random</code> object.
*
* @author Gary D. Gregory
* @since 2.0
* @version $Id: RandomUtils.java 471626 2006-11-06 04:02:09Z bayard $
*/
public class RandomUtils
{
/**
* An instance of {@link JVMRandom}.
*/
public static final Random JVM_RANDOM = new JVMRandom();
// should be possible for JVM_RANDOM?
// public static void nextBytes(byte[]) {
// public synchronized double nextGaussian();
// }
/**
* <p>
* Returns the next pseudorandom, uniformly distributed int value from the Math.random() sequence.
* </p>
*
* @return the random int
*/
public static int nextInt()
{
return nextInt(JVM_RANDOM);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed int value from the given <code>random</code> sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @return the random int
*/
public static int nextInt(Random random)
{
return random.nextInt();
}
/**
* <p>
* Returns a pseudorandom, uniformly distributed int value between <code>0</code> (inclusive) and the specified value (exclusive), from the Math.random() sequence.
* </p>
*
* @param n
* the specified exclusive max-value
* @return the random int
*/
public static int nextInt(int n)
{
return nextInt(JVM_RANDOM, n);
}
/**
* <p>
* Returns a pseudorandom, uniformly distributed int value between <code>0</code> (inclusive) and the specified value (exclusive), from the given Random sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @param n
* the specified exclusive max-value
* @return the random int
*/
public static int nextInt(Random random, int n)
{
// check this cannot return 'n'
return random.nextInt(n);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed long value from the Math.random() sequence.
* </p>
*
* @return the random long
*/
public static long nextLong()
{
return nextLong(JVM_RANDOM);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed long value from the given Random sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @return the random long
*/
public static long nextLong(Random random)
{
return random.nextLong();
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed boolean value from the Math.random() sequence.
* </p>
*
* @return the random boolean
*/
public static boolean nextBoolean()
{
return nextBoolean(JVM_RANDOM);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed boolean value from the given random sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @return the random boolean
*/
public static boolean nextBoolean(Random random)
{
return random.nextBoolean();
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed float value between <code>0.0</code> and <code>1.0</code> from the Math.random() sequence.
* </p>
*
* @return the random float
*/
public static float nextFloat()
{
return nextFloat(JVM_RANDOM);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed float value between <code>0.0</code> and <code>1.0</code> from the given Random sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @return the random float
*/
public static float nextFloat(Random random)
{
return random.nextFloat();
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed float value between <code>0.0</code> and <code>1.0</code> from the Math.random() sequence.
* </p>
*
* @return the random double
*/
public static double nextDouble()
{
return nextDouble(JVM_RANDOM);
}
/**
* <p>
* Returns the next pseudorandom, uniformly distributed float value between <code>0.0</code> and <code>1.0</code> from the given Random sequence.
* </p>
*
* @param random
* the Random sequence generator.
* @return the random double
*/
public static double nextDouble(Random random)
{
return random.nextDouble();
}
}