Package org.jboss.netty.util.internal

Class ThreadLocalRandom

java.lang.Object

java.util.Random

org.jboss.netty.util.internal.ThreadLocalRandom

All Implemented Interfaces:

Serializable

public final class ThreadLocalRandom
extends Random

A random number generator isolated to the current thread. Like the global Random generator used by the Math class, a ThreadLocalRandom is initialized with an internally generated seed that may not otherwise be modified. When applicable, use of ThreadLocalRandom rather than shared Random objects in concurrent programs will typically encounter much less overhead and contention. Use of ThreadLocalRandom is particularly appropriate when multiple tasks use random numbers in parallel in thread pools.

Usages of this class should typically be of the form: ThreadLocalRandom.current().nextX(...) (where X is Int, Long, etc). When all usages are of this form, it is never possible to accidently share a ThreadLocalRandom across multiple threads.

This class also provides additional commonly used bounded random generation methods.

Since:

1.7

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
ThreadLocalRandom()

Method Summary

Modifier and Type	Method	Description
static ThreadLocalRandom	current()	Returns the current thread's ThreadLocalRandom.
protected int	next(int bits)
void	setSeed(long seed)	Throws UnsupportedOperationException.

Methods inherited from class java.util.Random

doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextBoolean, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ThreadLocalRandom

public ThreadLocalRandom()

Method Details

current

public static ThreadLocalRandom current()

Returns the current thread's ThreadLocalRandom.

Returns:

the current thread's ThreadLocalRandom

setSeed

public void setSeed(long seed)

Throws UnsupportedOperationException. Setting seeds in this generator is not supported.

Overrides:

setSeed in class Random

Throws:

UnsupportedOperationException - always

next

protected int next(int bits)

Overrides:

next in class Random