Package io.github.pr0methean.betterrandom.prng.adapter

Class ReseedingThreadLocalRandomWrapper<T extends BaseRandom>

java.lang.Object

java.util.Random

io.github.pr0methean.betterrandom.prng.BaseRandom

io.github.pr0methean.betterrandom.prng.adapter.RandomWrapper<T>

io.github.pr0methean.betterrandom.prng.adapter.ThreadLocalRandomWrapper<T>

io.github.pr0methean.betterrandom.prng.adapter.ReseedingThreadLocalRandomWrapper<T>

All Implemented Interfaces:

ByteArrayReseedableRandom, EntropyCountingRandom, RepeatableRandom, Dumpable, Serializable

public class ReseedingThreadLocalRandomWrapper<T extends BaseRandom>
extends ThreadLocalRandomWrapper<T>

A ThreadLocalRandomWrapper that reseeds all its instances using a RandomSeeder.

See Also:

Serialized Form

Field Summary

Fields inherited from class io.github.pr0methean.betterrandom.prng.adapter.ThreadLocalRandomWrapper

threadLocal

Fields inherited from class io.github.pr0methean.betterrandom.prng.BaseRandom

ENTROPY_OF_DOUBLE, ENTROPY_OF_FLOAT, entropyBits, lock, randomSeeder, seed, superConstructorFinished

Constructor Summary

Constructors

Constructor	Description
ReseedingThreadLocalRandomWrapper(int seedSize, SeedGenerator seedGenerator, SerializableFunction<byte[],? extends T> creator)	Wraps a seed generator and a function that takes a seed byte array as input.
ReseedingThreadLocalRandomWrapper(SeedGenerator seedGenerator, SerializableSupplier<? extends T> initializer)	Wraps the given SerializableSupplier.
ReseedingThreadLocalRandomWrapper(SerializableSupplier<? extends T> initializer, RandomSeeder randomSeederThread)	Wraps the given SerializableSupplier.

Method Summary

Modifier and Type	Method	Description
RandomSeeder	getRandomSeeder()	Returns the current seed generator for this PRNG.
void	setRandomSeeder(RandomSeeder randomSeeder)	Not supported, because this class uses a thread-local seed.
static ReseedingThreadLocalRandomWrapper<BaseRandom>	wrapLegacy(SerializableLongFunction<Random> legacyCreator, SeedGenerator seedGenerator)	Uses this class and RandomWrapper to decorate any implementation of Random that can be constructed from a long seed into a fully-concurrent one.

Methods inherited from class io.github.pr0methean.betterrandom.prng.adapter.ThreadLocalRandomWrapper

addSubclassFields, debitEntropy, getEntropyBits, getNewSeedLength, getSeed, getWrapped, initTransientFields, nextBoolean, nextBytes, nextDouble, nextDoubleNoEntropyDebit, nextFloat, nextGaussian, nextInt, nextInt, nextInt, nextLong, nextLong, nextLong, nextLongNoEntropyDebit, preferSeedWithLong, setSeed, setSeedInternal, withProbability, withProbabilityInternal

Methods inherited from class io.github.pr0methean.betterrandom.prng.adapter.RandomWrapper

next, setInitiallyKnownSeed, setWrapped, supportsMultipleSeedLengths, toString, usesParallelStreams, wrapJavaUtilRandom, wrapJavaUtilRandom, wrapJavaUtilRandom, wrapSecureRandom

Methods inherited from class io.github.pr0methean.betterrandom.prng.BaseRandom

checkLength, checkValidRange, creditEntropyForNewSeed, doubles, doubles, doubles, doubles, dump, entropyOfInt, entropyOfLong, fallbackSetSeedIfInitialized, gaussians, gaussians, internalNextGaussian, ints, ints, ints, ints, lockForNextGaussian, longs, longs, longs, longs, nextDouble, nextDouble, nextElement, nextElement, nextEnum, setSeed, unlockForNextGaussian

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.github.pr0methean.betterrandom.EntropyCountingRandom

needsReseedingEarly

Constructor Detail

ReseedingThreadLocalRandomWrapper

public ReseedingThreadLocalRandomWrapper(SeedGenerator seedGenerator,
                                         SerializableSupplier<? extends T> initializer)

Wraps the given SerializableSupplier. Uses the given RandomSeeder to reseed PRNGs, but not to initialize them unless the SerializableSupplier does so. This PRNG will be serializable as long as the SerializableSupplier's captures are serializable.

Parameters:

initializer - a supplier that will be called to provide the initial BaseRandom for each thread.

seedGenerator - The seed generation strategy whose RandomSeeder will be used to reseed each thread's PRNG.

ReseedingThreadLocalRandomWrapper

public ReseedingThreadLocalRandomWrapper(SerializableSupplier<? extends T> initializer,
                                         RandomSeeder randomSeederThread)

Wraps the given SerializableSupplier. Uses the given RandomSeeder to reseed PRNGs, but not to initialize them unless the SerializableSupplier does so. This PRNG will be serializable if the SerializableSupplier's captures are serializable.

Parameters:

initializer - a supplier that will be called to provide the initial BaseRandom for each thread

randomSeederThread - a random seeder that will reseed the PRNG for each thread when necessary

ReseedingThreadLocalRandomWrapper

public ReseedingThreadLocalRandomWrapper(int seedSize,
                                         SeedGenerator seedGenerator,
                                         SerializableFunction<byte[],? extends T> creator)
                                  throws SeedException

Wraps a seed generator and a function that takes a seed byte array as input. This ReseedingThreadLocalRandomWrapper will be serializable if the SerializableFunction's captures are serializable.

Parameters:

seedSize - the size of seed arrays to generate.

seedGenerator - The seed generation strategy that will provide the seed value for each thread's BaseRandom, both at initialization and through the corresponding RandomSeeder.

creator - a SerializableFunction that creates a BaseRandom from each seed. Probably a constructor reference.

Throws:

SeedException - if seedGenerator fails to generate an initial seed

Method Detail

wrapLegacy

public static ReseedingThreadLocalRandomWrapper<BaseRandom> wrapLegacy(SerializableLongFunction<Random> legacyCreator,
                                                                       SeedGenerator seedGenerator)

Uses this class and RandomWrapper to decorate any implementation of Random that can be constructed from a long seed into a fully-concurrent one.

Parameters:

legacyCreator - a function that provides the Random that underlies the returned wrapper on each thread, taking a seed as input.

seedGenerator - the seed generator whose output will be fed to legacyCreator.

Returns:

a ThreadLocalRandomWrapper decorating instances created by legacyCreator.

setRandomSeeder

public void setRandomSeeder(RandomSeeder randomSeeder)

Description copied from class: ThreadLocalRandomWrapper

Not supported, because this class uses a thread-local seed.

Overrides:

setRandomSeeder in class ThreadLocalRandomWrapper<T extends BaseRandom>

Parameters:

randomSeeder - ignored.

getRandomSeeder

public RandomSeeder getRandomSeeder()

Description copied from class: BaseRandom

Returns the current seed generator for this PRNG.

Overrides:

getRandomSeeder in class ThreadLocalRandomWrapper<T extends BaseRandom>

Returns:

the current seed generator, or null if there is none