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

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