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 /**

  * Classes and interfaces that support the definition and use of "random generators", a term that

  * is meant to cover what have traditionally been called "random number generators" as well as

  * generators of other sorts of randomly chosen values, and also to cover not only deterministic

  * (pseudorandom) algorithms but also generators of values that use some "truly random" physical

  * source (perhaps making use of thermal noise, for example, or quantum-mechanical effects).

  *

  * The principal interface is {@link java.util.random.RandomGenerator}, which provides methods

  * for requesting individual values of type {@code int}, {@code long}, {@code float}, {@code double}, or {@code boolean}

  * chosen (pseudo)randomly from a uniform distribution; methods for requesting values of type {@code double}

  * chosen (pseudo)randomly from a normal distribution or from an exponential distribution;

  * and methods for creating streams of (pseudo)randomly chosen values of type {@code int}, {@code long}, or {@code double}.

  * These streams are spliterator-based, allowing for parallel processing of their elements.

  *

  * An important subsidiary interface is {@link java.util.random.RandomGenerator.StreamableGenerator},

  * which provides methods for creating spliterator-based streams of {@code RandomGenerator} objects,

  * allowing for allowing for parallel processing of these objects using multiple threads.

  * Unlike {@link java.util.Random}, most implementations of {@code java.util.random.RandomGenerator}

  * are <i>not</i> thread-safe.  The intent is that instances should not be shared among threads;

  * rather, each thread should have its own random generator(s) to use.  The various pseudorandom algorithms

  * provided by this package are designed so that multiple instances will (with very high probability) behave as

  * if statistically independent.

  *

  * Historically, most pseudorandom generator algorithms have been based on some sort of

  * finite-state machine with a single, large cycle of states; when it is necessary to have

  * multiple threads use the same algorithm simultaneously, the usual technique is to arrange for

  * each thread to traverse a different region of the state cycle.  These regions may be doled out

  * to threads by starting with a single initial state and then using a "jump function" that

  * travels a long distance around the cycle (perhaps 2<sup>64</sup> steps or more); the jump function is applied repeatedly

  * and sequentially, to identify widely spaced initial states for each thread's generator.  This strategy is

  * supported by the interface {@link java.util.random.RandomGenerator.JumpableGenerator}.

  * Sometimes it is desirable to support two levels of jumping (by long distances and

  * by <i>really</i> long distances); this strategy is supported by the interface

  * {@link java.util.random.RandomGenerator.LeapableGenerator}.  There is also an interface

  * {@link java.util.random.RandomGenerator.ArbitrarilyJumpableGenerator} for algorithms that

  * allow jumping along the state cycle by any user-specified distance.

  * In this package, implementations of these interfaces include

  * {@link java.util.random.Xoroshiro128PlusPlus},

  * {@link java.util.random.Xoroshiro128StarStar},

  * {@link java.util.random.Xoshiro256StarStar},

  * and {@link java.util.random.MRG32K3A}.

  *

  * A more recent category of "splittable" pseudorandom generator algorithms uses a large family

  * of state cycles and makes some attempt to ensure that distinct instances use different state

  * cycles; but even if two instances "accidentally" use the same state cycle, they are highly

  * likely to traverse different regions parts of that shared state cycle.  This strategy is

  * supported by the interface {@link java.util.random.RandomGenerator.SplittableGenerator}.

  * In this package, implementations of this interface include

  * {@link java.util.random.L32X64MixRandom},

  * {@link java.util.random.L64X128MixRandom},

  * {@link java.util.random.L64X128PlusPlusRandom},

  * {@link java.util.random.L64X128StarStarMixRandom},

  * {@link java.util.random.L64X256MixRandom},

  * {@link java.util.random.L64X1024MixRandom},

  * {@link java.util.random.L128X128MixRandom},

  * {@link java.util.random.L128X128PlusPlusRandom},

  * {@link java.util.random.L128X128StarStarMixRandom},

  * {@link java.util.random.L128X256MixRandom},

  * {@link java.util.random.L128X1024MixRandom},

  * and {@link java.util.SplittableRandom}.

  * Generally speaking, among the "{@code LmmmXnnn}" generators, the state size of the generator is

  * {@code (mmm - 1 + nnn)} bits and the memory required for an instance is {@code (2 * mmm + nnn)} bits;

  * larger values of "{@code mmm}" imply a lower probability that two instances will traverse the

  * same state cycle; and larger values of "{@code nnn}" imply that the generator is equidistributed

  * in a larger number of dimensions.  A class with "{@code Mix}" in its name uses a strong mixing

  * function with excellent avalanche characteristics; a class with "{@code StarStar}" or "{@code PlusPlus}"

  * in its name uses a weaker but faster mixing function.  See the documentation for individual classes

  * for details about their specific characteristics.

  *

  * The class {@link java.util.random.RandomSupport} provides utility methods, constants, and

  * abstract classes frequently useful in the implementation of pseudorandom number generators

  * that satisfy the interface {@link RandomGenerator}.

  *

  * @since 14

  */

 package java.util.random;