Interface RandomGenerator.SplittableGenerator

All Superinterfaces:

RandomGenerator, RandomGenerator.StreamableGenerator

All Known Implementing Classes:

SplittableRandom

Enclosing interface:

RandomGenerator

public static interface RandomGenerator.SplittableGenerator
extends RandomGenerator.StreamableGenerator

This interface is designed to provide a common protocol for objects that generate sequences of pseudorandom values and can be split into two objects (the original one and a new one) each of which obey that same protocol (and therefore can be recursively split indefinitely).

Ideally, all RandomGenerator.SplittableGenerator objects produced by recursive splitting from a single original RandomGenerator.SplittableGenerator object are statistically independent of one another and individually uniform. Therefore we would expect the set of values collectively generated by a set of such objects to have the same statistical properties as if the same quantity of values were generated by a single thread using a single RandomGenerator.SplittableGenerator object. In practice, one must settle for some approximation to independence and uniformity.

Methods are provided to perform a single splitting operation and also to produce a stream of generators split off from the original (by either iterative or recursive splitting, or a combination).

Objects that implement RandomGenerator.SplittableGenerator are typically not cryptographically secure. Consider instead using SecureRandom to get a cryptographically secure pseudo-random number generator for use by security-sensitive applications.

Since:

17

Nested Class Summary

Nested classes/interfaces declared in interface RandomGenerator

RandomGenerator.ArbitrarilyJumpableGenerator, RandomGenerator.JumpableGenerator, RandomGenerator.LeapableGenerator, RandomGenerator.SplittableGenerator, RandomGenerator.StreamableGenerator

Modifier and Type	Interface	Description
static interface	RandomGenerator.ArbitrarilyJumpableGenerator	This interface is designed to provide a common protocol for objects that generate sequences of pseudorandom values and can easily jump forward, by an arbitrary amount, to a distant point in the state cycle.
static interface	RandomGenerator.JumpableGenerator	This interface is designed to provide a common protocol for objects that generate pseudorandom values and can easily jump forward, by a moderate amount (ex. 264) to a distant point in the state cycle.
static interface	RandomGenerator.LeapableGenerator	This interface is designed to provide a common protocol for objects that generate sequences of pseudorandom values and can easily not only jump but also leap forward, by a large amount (ex. 2128), to a very distant point in the state cycle.
static interface	RandomGenerator.SplittableGenerator	This interface is designed to provide a common protocol for objects that generate sequences of pseudorandom values and can be split into two objects (the original one and a new one) each of which obey that same protocol (and therefore can be recursively split indefinitely).
static interface	RandomGenerator.StreamableGenerator	The RandomGenerator.StreamableGenerator interface augments the RandomGenerator interface to provide methods that return streams of RandomGenerator objects.

Method Summary

Modifier and Type	Method	Description
static RandomGenerator.SplittableGenerator	of(String name)	Returns an instance of RandomGenerator.SplittableGenerator that utilizes the name algorithm.
default Stream<RandomGenerator>	rngs()	Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator interface.
default Stream<RandomGenerator>	rngs(long streamSize)	Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator interface.
RandomGenerator.SplittableGenerator	split()	Returns a new pseudorandom number generator, split off from this one, that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces.
RandomGenerator.SplittableGenerator	split(RandomGenerator.SplittableGenerator source)	Returns a new pseudorandom number generator, split off from this one, that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces.
default Stream<RandomGenerator.SplittableGenerator>	splits()	Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.
Stream<RandomGenerator.SplittableGenerator>	splits(long streamSize)	Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.
Stream<RandomGenerator.SplittableGenerator>	splits(long streamSize, RandomGenerator.SplittableGenerator source)	Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.
Stream<RandomGenerator.SplittableGenerator>	splits(RandomGenerator.SplittableGenerator source)	Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.

Methods declared in interface RandomGenerator

doubles, doubles, doubles, doubles, equiDoubles, ints, ints, ints, ints, isDeprecated, longs, longs, longs, longs, nextBoolean, nextBytes, nextDouble, nextDouble, nextDouble, nextExponential, nextFloat, nextFloat, nextFloat, nextGaussian, nextGaussian, nextInt, nextInt, nextInt, nextLong, nextLong, nextLong

Modifier and Type	Method	Description
default DoubleStream	doubles()	Returns an effectively unlimited stream of pseudorandomly chosen double values.
default DoubleStream	doubles(double randomNumberOrigin, double randomNumberBound)	Returns an effectively unlimited stream of pseudorandomly chosen double values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default DoubleStream	doubles(long streamSize)	Returns a stream producing the given streamSize number of pseudorandomly chosen double values.
default DoubleStream	doubles(long streamSize, double randomNumberOrigin, double randomNumberBound)	Returns a stream producing the given streamSize number of pseudorandomly chosen double values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default DoubleStream	equiDoubles(double left, double right, boolean isLeftIncluded, boolean isRightIncluded)	Returns an effectively unlimited stream of pseudorandomly chosen double values, where each value is between the specified left boundary and the specified right boundary.
default IntStream	ints()	Returns an effectively unlimited stream of pseudorandomly chosen int values.
default IntStream	ints(int randomNumberOrigin, int randomNumberBound)	Returns an effectively unlimited stream of pseudorandomly chosen int values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default IntStream	ints(long streamSize)	Returns a stream producing the given streamSize number of pseudorandomly chosen int values.
default IntStream	ints(long streamSize, int randomNumberOrigin, int randomNumberBound)	Returns a stream producing the given streamSize number of pseudorandomly chosen int values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default boolean	isDeprecated()	Return true if the implementation of RandomGenerator (algorithm) has been marked for deprecation.
default LongStream	longs()	Returns an effectively unlimited stream of pseudorandomly chosen long values.
default LongStream	longs(long streamSize)	Returns a stream producing the given streamSize number of pseudorandomly chosen long values.
default LongStream	longs(long randomNumberOrigin, long randomNumberBound)	Returns an effectively unlimited stream of pseudorandomly chosen long values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default LongStream	longs(long streamSize, long randomNumberOrigin, long randomNumberBound)	Returns a stream producing the given streamSize number of pseudorandomly chosen long values, where each value is between the specified origin (inclusive) and the specified bound (exclusive).
default boolean	nextBoolean()	Returns a pseudorandomly chosen boolean value.
default void	nextBytes(byte[] bytes)	Fills a user-supplied byte array with generated byte values pseudorandomly chosen uniformly from the range of values between -128 (inclusive) and 127 (inclusive).
default double	nextDouble()	Returns a pseudorandom double value between zero (inclusive) and one (exclusive).
default double	nextDouble(double bound)	Returns a pseudorandomly chosen double value between zero (inclusive) and the specified bound (exclusive).
default double	nextDouble(double origin, double bound)	Returns a pseudorandomly chosen double value between the specified origin (inclusive) and the specified bound (exclusive).
default double	nextExponential()	Returns a nonnegative double value pseudorandomly chosen from an exponential distribution whose mean is 1.
default float	nextFloat()	Returns a pseudorandom float value between zero (inclusive) and one (exclusive).
default float	nextFloat(float bound)	Returns a pseudorandomly chosen float value between zero (inclusive) and the specified bound (exclusive).
default float	nextFloat(float origin, float bound)	Returns a pseudorandomly chosen float value between the specified origin (inclusive) and the specified bound (exclusive).
default double	nextGaussian()	Returns a double value pseudorandomly chosen from a Gaussian (normal) distribution whose mean is 0 and whose standard deviation is 1.
default double	nextGaussian(double mean, double stddev)	Returns a double value pseudorandomly chosen from a Gaussian (normal) distribution with a mean and standard deviation specified by the arguments.
default int	nextInt()	Returns a pseudorandomly chosen int value.
default int	nextInt(int bound)	Returns a pseudorandomly chosen int value between zero (inclusive) and the specified bound (exclusive).
default int	nextInt(int origin, int bound)	Returns a pseudorandomly chosen int value between the specified origin (inclusive) and the specified bound (exclusive).
long	nextLong()	Returns a pseudorandomly chosen long value.
default long	nextLong(long bound)	Returns a pseudorandomly chosen long value between zero (inclusive) and the specified bound (exclusive).
default long	nextLong(long origin, long bound)	Returns a pseudorandomly chosen long value between the specified origin (inclusive) and the specified bound (exclusive).

Method Details

of

static RandomGenerator.SplittableGenerator of(String name)

Returns an instance of RandomGenerator.SplittableGenerator that utilizes the name algorithm.

Parameters:

name - Name of random number generator algorithm

Returns:

An instance of RandomGenerator.SplittableGenerator

Throws:

NullPointerException - if name is null

IllegalArgumentException - if the named algorithm is not found

split

RandomGenerator.SplittableGenerator split()

Returns a new pseudorandom number generator, split off from this one, that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces.

This pseudorandom number generator may be used as a source of pseudorandom bits used to initialize the state of the new one.

Returns:

a new object that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces

split

RandomGenerator.SplittableGenerator split(RandomGenerator.SplittableGenerator source)

Returns a new pseudorandom number generator, split off from this one, that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces.

Parameters:

source - a RandomGenerator.SplittableGenerator instance to be used instead of this one as a source of pseudorandom bits used to initialize the state of the new ones.

Returns:

an object that implements the RandomGenerator and RandomGenerator.SplittableGenerator interfaces

Throws:

NullPointerException - if source is null

splits

default Stream<RandomGenerator.SplittableGenerator> splits()

Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.

This pseudorandom number generator may be used as a source of pseudorandom bits used to initialize the state the new ones.

Implementation Requirements:

The default implementation invokes splits(this).

Implementation Note:

It is permitted to implement this method in a manner equivalent to splits (Long.MAX_VALUE).

Returns:

a stream of RandomGenerator.SplittableGenerator objects

splits

Stream<RandomGenerator.SplittableGenerator> splits(long streamSize)

Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.

This pseudorandom number generator may be used as a source of pseudorandom bits used to initialize the state the new ones.

Parameters:

streamSize - the number of values to generate

Returns:

a stream of RandomGenerator.SplittableGenerator objects

Throws:

IllegalArgumentException - if streamSize is less than zero

splits

Stream<RandomGenerator.SplittableGenerator> splits(RandomGenerator.SplittableGenerator source)

Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.

Implementation Note:

It is permitted to implement this method in a manner equivalent to splits (Long.MAX_VALUE, source).

Parameters:

source - a RandomGenerator.SplittableGenerator instance to be used instead of this one as a source of pseudorandom bits used to initialize the state of the new ones.

Returns:

a stream of RandomGenerator.SplittableGenerator objects

Throws:

NullPointerException - if source is null

splits

Stream<RandomGenerator.SplittableGenerator> splits(long streamSize,
 RandomGenerator.SplittableGenerator source)

Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator.SplittableGenerator interface.

Parameters:

streamSize - the number of values to generate

source - a RandomGenerator.SplittableGenerator instance to be used instead of this one as a source of pseudorandom bits used to initialize the state of the new ones.

Returns:

a stream of RandomGenerator.SplittableGenerator objects

Throws:

IllegalArgumentException - if streamSize is less than zero

NullPointerException - if source is null

rngs

default Stream<RandomGenerator> rngs()

Returns an effectively unlimited stream of new pseudorandom number generators, each of which implements the RandomGenerator interface. Ideally the generators in the stream will appear to be statistically independent.

Specified by:

rngs in interface RandomGenerator.StreamableGenerator

Implementation Requirements:

The default implementation calls splits().

Returns:

a stream of objects that implement the RandomGenerator interface

rngs

default Stream<RandomGenerator> rngs(long streamSize)

Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the RandomGenerator interface. Ideally the generators in the stream will appear to be statistically independent.

Specified by:

rngs in interface RandomGenerator.StreamableGenerator

Implementation Requirements:

The default implementation calls splits(streamSize).

Parameters:

streamSize - the number of generators to generate

Returns:

a stream of objects that implement the RandomGenerator interface

Throws:

IllegalArgumentException - if streamSize is less than zero