Added in API level 35

RandomGenerator.SplittableGenerator

public static interface RandomGenerator.SplittableGenerator
implements RandomGenerator.StreamableGenerator

java.util.random.RandomGenerator.SplittableGenerator
SplittableRandom A generator of uniform pseudorandom values (with period 264) applicable for use in (among other contexts) isolated parallel computations that may generate subtasks. 


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 SplittableGenerator objects produced by recursive splitting from a single original 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 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 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.

Summary

Public methods

static RandomGenerator.SplittableGenerator of(String name)

Returns an instance of SplittableGenerator that utilizes the name algorithm.

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.

default Stream<RandomGenerator> rngs()

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

abstract RandomGenerator.SplittableGenerator split(RandomGenerator.SplittableGenerator source)

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

abstract RandomGenerator.SplittableGenerator split()

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

default Stream<RandomGenerator.SplittableGenerator> splits()

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

abstract 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 SplittableGenerator interface.

abstract Stream<RandomGenerator.SplittableGenerator> splits(long streamSize)

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

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

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

Inherited methods

static RandomGenerator.StreamableGenerator of(String name)

Returns an instance of StreamableGenerator that utilizes the name algorithm.

default Stream<RandomGenerator> rngs(long streamSize)

Returns an effectively unlimited stream of objects, each of which implements the RandomGenerator interface.

abstract Stream<RandomGenerator> rngs()

Returns an effectively unlimited stream of objects, each of which implements the RandomGenerator interface.

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 doubles(long streamSize)

Returns a stream producing the given streamSize number of pseudorandomly chosen double values.

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).

static RandomGenerator getDefault()

Returns a RandomGenerator meeting the minimal requirement of having an algorithm whose state bits are greater than or equal 64.

default IntStream ints(long streamSize)

Returns a stream producing the given streamSize number 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()

Returns an effectively unlimited stream 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(long streamSize)

Returns a stream producing the given streamSize number of pseudorandomly chosen long values.

default LongStream longs()

Returns an effectively unlimited stream 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(float origin, float bound)

Returns a pseudorandomly chosen float value between the specified origin (inclusive) and the specified bound (exclusive).

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 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 double nextGaussian()

Returns a double value pseudorandomly chosen from a Gaussian (normal) distribution whose mean is 0 and whose standard deviation is 1.

default int nextInt(int origin, int bound)

Returns a pseudorandomly chosen int value between the specified origin (inclusive) and the specified bound (exclusive).

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 long nextLong(long origin, long bound)

Returns a pseudorandomly chosen long value between the specified origin (inclusive) and the specified bound (exclusive).

default long nextLong(long bound)

Returns a pseudorandomly chosen long value between zero (inclusive) and the specified bound (exclusive).

abstract long nextLong()

Returns a pseudorandomly chosen long value.

static RandomGenerator of(String name)

Returns an instance of RandomGenerator that utilizes the name algorithm.

Public methods

of

Added in API level 35
public static RandomGenerator.SplittableGenerator of (String name)

Returns an instance of SplittableGenerator that utilizes the name algorithm.

Parameters
name String: Name of random number generator algorithm

Throws
NullPointerException if name is null
IllegalArgumentException if the named algorithm is not found

rngs

Added in API level 35
public 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.

Implementation Requirements:
  • The default implementation calls splits(streamSize).
Parameters
streamSize long: the number of generators to generate

Returns
Stream<RandomGenerator> a stream of objects that implement the RandomGenerator interface

Throws
IllegalArgumentException if streamSize is less than zero

rngs

Added in API level 35
public 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.

Implementation Requirements:
  • The default implementation calls splits().
Returns
Stream<RandomGenerator> a stream of objects that implement the RandomGenerator interface

split

Added in API level 35
public abstract RandomGenerator.SplittableGenerator split (RandomGenerator.SplittableGenerator source)

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

Parameters
source RandomGenerator.SplittableGenerator: a 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
RandomGenerator.SplittableGenerator an object that implements the RandomGenerator and SplittableGenerator interfaces

Throws
NullPointerException if source is null

split

Added in API level 35
public abstract RandomGenerator.SplittableGenerator split ()

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

splits

Added in API level 35
public Stream<RandomGenerator.SplittableGenerator> splits ()

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

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

Implementation Note:
Implementation Requirements:

splits

Added in API level 35
public abstract 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 SplittableGenerator interface.

Parameters
streamSize long: the number of values to generate

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

Throws
IllegalArgumentException if streamSize is less than zero
NullPointerException if source is null

splits

Added in API level 35
public abstract Stream<RandomGenerator.SplittableGenerator> splits (long streamSize)

Returns a stream producing the given streamSize number of new pseudorandom number generators, each of which implements the 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 long: the number of values to generate

Throws
IllegalArgumentException if streamSize is less than zero

splits

Added in API level 35
public abstract Stream<RandomGenerator.SplittableGenerator> splits (RandomGenerator.SplittableGenerator source)

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

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

Throws
NullPointerException if source is null