ThreadLocalRandom

public 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 (for example, each a ForkJoinTask) 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.

Instances of ThreadLocalRandom are not cryptographically secure. Consider instead using SecureRandom in security-sensitive applications. Additionally, default-constructed instances do not use a cryptographically random seed unless the {@linkplain System#getProperty system property} java.util.secureRandomSeed is set to true.

Public Method Summary

static ThreadLocalRandom
current()
Returns the current thread's ThreadLocalRandom.
DoubleStream
doubles(long streamSize, double randomNumberOrigin, double randomNumberBound)
Returns a stream producing the given streamSize number of pseudorandom double values, each conforming to the given origin (inclusive) and bound (exclusive).
DoubleStream
doubles(long streamSize)
Returns a stream producing the given streamSize number of pseudorandom double values, each between zero (inclusive) and one (exclusive).
DoubleStream
doubles()
Returns an effectively unlimited stream of pseudorandom double values, each between zero (inclusive) and one (exclusive).
DoubleStream
doubles(double randomNumberOrigin, double randomNumberBound)
Returns an effectively unlimited stream of pseudorandom double values, each conforming to the given origin (inclusive) and bound (exclusive).
IntStream
ints(long streamSize)
Returns a stream producing the given streamSize number of pseudorandom int values.
IntStream
ints(int randomNumberOrigin, int randomNumberBound)
Returns an effectively unlimited stream of pseudorandom int values, each conforming to the given origin (inclusive) a