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	/*
	* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.util;

	import java.util.concurrent.atomic.AtomicLong;
	import java.util.function.IntConsumer;
	import java.util.function.LongConsumer;
	import java.util.function.DoubleConsumer;
	import java.util.stream.StreamSupport;
	import java.util.stream.IntStream;
	import java.util.stream.LongStream;
	import java.util.stream.DoubleStream;

	/**
	* A generator of uniform pseudorandom values applicable for use in
	* (among other contexts) isolated parallel computations that may
	* generate subtasks. Class {@code SplittableRandom} supports methods for
	* producing pseudorandom numbers of type {@code int}, {@code long},
	* and {@code double} with similar usages as for class
	* {@link java.util.Random} but differs in the following ways:
	*
	* <ul>
	*
	* <li>Series of generated values pass the DieHarder suite testing
	* independence and uniformity properties of random number generators.
	* (Most recently validated with <a
	* href="http://www.phy.duke.edu/~rgb/General/dieharder.php"> version
	* 3.31.1</a>.) These tests validate only the methods for certain
	* types and ranges, but similar properties are expected to hold, at
	* least approximately, for others as well. The <em>period</em>
	* (length of any series of generated values before it repeats) is at
	* least 2<sup>64</sup>. </li>
	*
	* <li> Method {@link #split} constructs and returns a new
	* SplittableRandom instance that shares no mutable state with the
	* current instance. However, with very high probability, the
	* values collectively generated by the two objects have the same
	* statistical properties as if the same quantity of values were
	* generated by a single thread using a single {@code
	* SplittableRandom} object. </li>
	*
	* <li>Instances of SplittableRandom are <em>not</em> thread-safe.
	* They are designed to be split, not shared, across threads. For
	* example, a {@link java.util.concurrent.ForkJoinTask
	* fork/join-style} computation using random numbers might include a
	* construction of the form {@code new
	* Subtask(aSplittableRandom.split()).fork()}.
	*
	* <li>This class provides additional methods for generating random
	* streams, that employ the above techniques when used in {@code
	* stream.parallel()} mode.</li>
	*
	* </ul>
	*
	* <p>Instances of {@code SplittableRandom} are not cryptographically
	* secure. Consider instead using {@link java.security.SecureRandom}
	* in security-sensitive applications. Additionally,
	* default-constructed instances do not use a cryptographically random
	* seed unless the {@linkplain System#getProperty system property}
	* {@code java.util.secureRandomSeed} is set to {@code true}.
	*
	* @author Guy Steele
	* @author Doug Lea
	* @since 1.8
	*/
	public final class SplittableRandom {

	/*
	* Implementation Overview.
	*
	* This algorithm was inspired by the "DotMix" algorithm by
	* Leiserson, Schardl, and Sukha "Deterministic Parallel
	* Random-Number Generation for Dynamic-Multithreading Platforms",
	* PPoPP 2012, as well as those in "Parallel random numbers: as
	* easy as 1, 2, 3" by Salmon, Morae, Dror, and Shaw, SC 2011. It
	* differs mainly in simplifying and cheapening operations.
	*
	* The primary update step (method nextSeed()) is to add a
	* constant ("gamma") to the current (64 bit) seed, forming a
	* simple sequence. The seed and the gamma values for any two
	* SplittableRandom instances are highly likely to be different.
	*
	* Methods nextLong, nextInt, and derivatives do not return the
	* sequence (seed) values, but instead a hash-like bit-mix of
	* their bits, producing more independently distributed sequences.
	* For nextLong, the mix64 function is based on David Stafford's
	* (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html)
	* "Mix13" variant of the "64-bit finalizer" function in Austin
	* Appleby's MurmurHash3 algorithm (see
	* http://code.google.com/p/smhasher/wiki/MurmurHash3). The mix32
	* function is based on Stafford's Mix04 mix function, but returns
	* the upper 32 bits cast as int.
	*
	* The split operation uses the current generator to form the seed
	* and gamma for another SplittableRandom. To conservatively
	* avoid potential correlations between seed and value generation,
	* gamma selection (method mixGamma) uses different
	* (Murmurhash3's) mix constants. To avoid potential weaknesses
	* in bit-mixing transformations, we restrict gammas to odd values
	* with at least 24 0-1 or 1-0 bit transitions. Rather than
	* rejecting candidates with too few or too many bits set, method
	* mixGamma flips some bits (which has the effect of mapping at
	* most 4 to any given gamma value). This reduces the effective
	* set of 64bit odd gamma values by about 2%, and serves as an
	* automated screening for sequence constant selection that is
	* left as an empirical decision in some other hashing and crypto
	* algorithms.
	*
	* The resulting generator thus transforms a sequence in which
	* (typically) many bits change on each step, with an inexpensive
	* mixer with good (but less than cryptographically secure)
	* avalanching.
	*
	* The default (no-argument) constructor, in essence, invokes
	* split() for a common "defaultGen" SplittableRandom. Unlike
	* other cases, this split must be performed in a thread-safe
	* manner, so we use an AtomicLong to represent the seed rather
	* than use an explicit SplittableRandom. To bootstrap the
	* defaultGen, we start off using a seed based on current time
	* unless the java.util.secureRandomSeed property is set. This
	* serves as a slimmed-down (and insecure) variant of SecureRandom
	* that also avoids stalls that may occur when using /dev/random.
	*
	* It is a relatively simple matter to apply the basic design here
	* to use 128 bit seeds. However, emulating 128bit arithmetic and
	* carrying around twice the state add more overhead than appears
	* warranted for current usages.
	*
	* File organization: First the non-public methods that constitute
	* the main algorithm, then the main public methods, followed by
	* some custom spliterator classes needed for stream methods.
	*/

	/**
	* The golden ratio scaled to 64bits, used as the initial gamma
	* value for (unsplit) SplittableRandoms.
	*/
	private static final long GOLDEN_GAMMA = 0x9e3779b97f4a7c15L;

	/**
	* The least non-zero value returned by nextDouble(). This value
	* is scaled by a random value of 53 bits to produce a result.
	*/
	private static final double DOUBLE_UNIT = 0x1.0p-53; // 1.0 / (1L << 53);

	/**
	* The seed. Updated only via method nextSeed.
	*/
	private long seed;

	/**
	* The step value.
	*/
	private final long gamma;

	/**
	* Internal constructor used by all others except default constructor.
	*/
	private SplittableRandom(long seed, long gamma) {
	this.seed = seed;
	this.gamma = gamma;
	}

	/**
	* Computes Stafford variant 13 of 64bit mix function.
	*/
	private static long mix64(long z) {
	z = (z ^ (z >>> 30)) * 0xbf58476d1ce4e5b9L;
	z = (z ^ (z >>> 27)) * 0x94d049bb133111ebL;
	return z ^ (z >>> 31);
	}

	/**
	* Returns the 32 high bits of Stafford variant 4 mix64 function as int.
	*/
	private static int mix32(long z) {
	z = (z ^ (z >>> 33)) * 0x62a9d9ed799705f5L;
	return (int)(((z ^ (z >>> 28)) * 0xcb24d0a5c88c35b3L) >>> 32);
	}

	/**
	* Returns the gamma value to use for a new split instance.
	*/
	private static long mixGamma(long z) {
	z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL; // MurmurHash3 mix constants
	z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L;
	z = (z ^ (z >>> 33)) \| 1L; // force to be odd
	int n = Long.bitCount(z ^ (z >>> 1)); // ensure enough transitions
	return (n < 24) ? z ^ 0xaaaaaaaaaaaaaaaaL : z;
	}

	/**
	* Adds gamma to seed.
	*/
	private long nextSeed() {
	return seed += gamma;
	}

	/**
	* The seed generator for default constructors.
	*/
	private static final AtomicLong defaultGen = new AtomicLong(initialSeed());

	private static long initialSeed() {
	String pp = java.security.AccessController.doPrivileged(
	new sun.security.action.GetPropertyAction(
	"java.util.secureRandomSeed"));
	if (pp != null && pp.equalsIgnoreCase("true")) {
	byte[] seedBytes = java.security.SecureRandom.getSeed(8);
	long s = (long)(seedBytes[0]) & 0xffL;
	for (int i = 1; i < 8; ++i)
	s = (s << 8) \| ((long)(seedBytes[i]) & 0xffL);
	return s;
	}
	return (mix64(System.currentTimeMillis()) ^
	mix64(System.nanoTime()));
	}

	// IllegalArgumentException messages
	static final String BadBound = "bound must be positive";
	static final String BadRange = "bound must be greater than origin";
	static final String BadSize = "size must be non-negative";

	/*
	* Internal versions of nextX methods used by streams, as well as
	* the public nextX(origin, bound) methods. These exist mainly to
	* avoid the need for multiple versions of stream spliterators
	* across the different exported forms of streams.
	*/

	/**
	* The form of nextLong used by LongStream Spliterators. If
	* origin is greater than bound, acts as unbounded form of
	* nextLong, else as bounded form.
	*
	* @param origin the least value, unless greater than bound
	* @param bound the upper bound (exclusive), must not equal origin
	* @return a pseudorandom value
	*/
	final long internalNextLong(long origin, long bound) {
	/*
	* Four Cases:
	*
	* 1. If the arguments indicate unbounded form, act as
	* nextLong().
	*
	* 2. If the range is an exact power of two, apply the
	* associated bit mask.
	*
	* 3. If the range is positive, loop to avoid potential bias
	* when the implicit nextLong() bound (2<sup>64</sup>) is not
	* evenly divisible by the range. The loop rejects candidates
	* computed from otherwise over-represented values. The
	* expected number of iterations under an ideal generator
	* varies from 1 to 2, depending on the bound. The loop itself
	* takes an unlovable form. Because the first candidate is
	* already available, we need a break-in-the-middle
	* construction, which is concisely but cryptically performed
	* within the while-condition of a body-less for loop.
	*
	* 4. Otherwise, the range cannot be represented as a positive
	* long. The loop repeatedly generates unbounded longs until
	* obtaining a candidate meeting constraints (with an expected
	* number of iterations of less than two).
	*/

	long r = mix64(nextSeed());
	if (origin < bound) {
	long n = bound - origin, m = n - 1;
	if ((n & m) == 0L) // power of two
	r = (r & m) + origin;
	else if (n > 0L) { // reject over-represented candidates
	for (long u = r >>> 1; // ensure nonnegative
	u + m - (r = u % n) < 0L; // rejection check
	u = mix64(nextSeed()) >>> 1) // retry
	;
	r += origin;
	}
	else { // range not representable as long
	while (r < origin \|\| r >= bound)
	r = mix64(nextSeed());
	}
	}
	return r;
	}

	/**
	* The form of nextInt used by IntStream Spliterators.
	* Exactly the same as long version, except for types.
	*
	* @param origin the least value, unless greater than bound
	* @param bound the upper bound (exclusive), must not equal origin
	* @return a pseudorandom value
	*/
	final int internalNextInt(int origin, int bound) {
	int r = mix32(nextSeed());
	if (origin < bound) {
	int n = bound - origin, m = n - 1;
	if ((n & m) == 0)
	r = (r & m) + origin;
	else if (n > 0) {
	for (int u = r >>> 1;
	u + m - (r = u % n) < 0;
	u = mix32(nextSeed()) >>> 1)
	;
	r += origin;
	}
	else {
	while (r < origin \|\| r >= bound)
	r = mix32(nextSeed());
	}
	}
	return r;
	}

	/**
	* The form of nextDouble used by DoubleStream Spliterators.
	*
	* @param origin the least value, unless greater than bound
	* @param bound the upper bound (exclusive), must not equal origin
	* @return a pseudorandom value
	*/
	final double internalNextDouble(double origin, double bound) {
	double r = (nextLong() >>> 11) * DOUBLE_UNIT;
	if (origin < bound) {
	r = r * (bound - origin) + origin;
	if (r >= bound) // correct for rounding
	r = Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1);
	}
	return r;
	}

	/* ---------------- public methods ---------------- */

	/**
	* Creates a new SplittableRandom instance using the specified
	* initial seed. SplittableRandom instances created with the same
	* seed in the same program generate identical sequences of values.
	*
	* @param seed the initial seed
	*/
	public SplittableRandom(long seed) {
	this(seed, GOLDEN_GAMMA);
	}

	/**
	* Creates a new SplittableRandom instance that is likely to
	* generate sequences of values that are statistically independent
	* of those of any other instances in the current program; and
	* may, and typically does, vary across program invocations.
	*/
	public SplittableRandom() { // emulate defaultGen.split()
	long s = defaultGen.getAndAdd(2 * GOLDEN_GAMMA);
	this.seed = mix64(s);
	this.gamma = mixGamma(s + GOLDEN_GAMMA);
	}

	/**
	* Constructs and returns a new SplittableRandom instance that
	* shares no mutable state with this instance. However, with very
	* high probability, the set of values collectively generated by
	* the two objects has the same statistical properties as if the
	* same quantity of values were generated by a single thread using
	* a single SplittableRandom object. Either or both of the two
	* objects may be further split using the {@code split()} method,
	* and the same expected statistical properties apply to the
	* entire set of generators constructed by such recursive
	* splitting.
	*
	* @return the new SplittableRandom instance
	*/
	public SplittableRandom split() {
	return new SplittableRandom(nextLong(), mixGamma(nextSeed()));
	}

	/**
	* Returns a pseudorandom {@code int} value.
	*
	* @return a pseudorandom {@code int} value
	*/
	public int nextInt() {
	return mix32(nextSeed());
	}

	/**
	* Returns a pseudorandom {@code int} value between zero (inclusive)
	* and the specified bound (exclusive).
	*
	* @param bound the upper bound (exclusive). Must be positive.
	* @return a pseudorandom {@code int} value between zero
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code bound} is not positive
	*/
	public int nextInt(int bound) {
	if (bound <= 0)
	throw new IllegalArgumentException(BadBound);
	// Specialize internalNextInt for origin 0
	int r = mix32(nextSeed());
	int m = bound - 1;
	if ((bound & m) == 0) // power of two
	r &= m;
	else { // reject over-represented candidates
	for (int u = r >>> 1;
	u + m - (r = u % bound) < 0;
	u = mix32(nextSeed()) >>> 1)
	;
	}
	return r;
	}

	/**
	* Returns a pseudorandom {@code int} value between the specified
	* origin (inclusive) and the specified bound (exclusive).
	*
	* @param origin the least value returned
	* @param bound the upper bound (exclusive)
	* @return a pseudorandom {@code int} value between the origin
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code origin} is greater than
	* or equal to {@code bound}
	*/
	public int nextInt(int origin, int bound) {
	if (origin >= bound)
	throw new IllegalArgumentException(BadRange);
	return internalNextInt(origin, bound);
	}

	/**
	* Returns a pseudorandom {@code long} value.
	*
	* @return a pseudorandom {@code long} value
	*/
	public long nextLong() {
	return mix64(nextSeed());
	}

	/**
	* Returns a pseudorandom {@code long} value between zero (inclusive)
	* and the specified bound (exclusive).
	*
	* @param bound the upper bound (exclusive). Must be positive.
	* @return a pseudorandom {@code long} value between zero
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code bound} is not positive
	*/
	public long nextLong(long bound) {
	if (bound <= 0)
	throw new IllegalArgumentException(BadBound);
	// Specialize internalNextLong for origin 0
	long r = mix64(nextSeed());
	long m = bound - 1;
	if ((bound & m) == 0L) // power of two
	r &= m;
	else { // reject over-represented candidates
	for (long u = r >>> 1;
	u + m - (r = u % bound) < 0L;
	u = mix64(nextSeed()) >>> 1)
	;
	}
	return r;
	}

	/**
	* Returns a pseudorandom {@code long} value between the specified
	* origin (inclusive) and the specified bound (exclusive).
	*
	* @param origin the least value returned
	* @param bound the upper bound (exclusive)
	* @return a pseudorandom {@code long} value between the origin
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code origin} is greater than
	* or equal to {@code bound}
	*/
	public long nextLong(long origin, long bound) {
	if (origin >= bound)
	throw new IllegalArgumentException(BadRange);
	return internalNextLong(origin, bound);
	}

	/**
	* Returns a pseudorandom {@code double} value between zero
	* (inclusive) and one (exclusive).
	*
	* @return a pseudorandom {@code double} value between zero
	* (inclusive) and one (exclusive)
	*/
	public double nextDouble() {
	return (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT;
	}

	/**
	* Returns a pseudorandom {@code double} value between 0.0
	* (inclusive) and the specified bound (exclusive).
	*
	* @param bound the upper bound (exclusive). Must be positive.
	* @return a pseudorandom {@code double} value between zero
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code bound} is not positive
	*/
	public double nextDouble(double bound) {
	if (!(bound > 0.0))
	throw new IllegalArgumentException(BadBound);
	double result = (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT * bound;
	return (result < bound) ? result : // correct for rounding
	Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1);
	}

	/**
	* Returns a pseudorandom {@code double} value between the specified
	* origin (inclusive) and bound (exclusive).
	*
	* @param origin the least value returned
	* @param bound the upper bound (exclusive)
	* @return a pseudorandom {@code double} value between the origin
	* (inclusive) and the bound (exclusive)
	* @throws IllegalArgumentException if {@code origin} is greater than
	* or equal to {@code bound}
	*/
	public double nextDouble(double origin, double bound) {
	if (!(origin < bound))
	throw new IllegalArgumentException(BadRange);
	return internalNextDouble(origin, bound);
	}

	/**
	* Returns a pseudorandom {@code boolean} value.
	*
	* @return a pseudorandom {@code boolean} value
	*/
	public boolean nextBoolean() {
	return mix32(nextSeed()) < 0;
	}

	// stream methods, coded in a way intended to better isolate for
	// maintenance purposes the small differences across forms.

	/**
	* Returns a stream producing the given {@code streamSize} number
	* of pseudorandom {@code int} values from this generator and/or
	* one split from it.
	*
	* @param streamSize the number of values to generate
	* @return a stream of pseudorandom {@code int} values
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero
	*/
	public IntStream ints(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(this, 0L, streamSize, Integer.MAX_VALUE, 0),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code int}
	* values from this generator and/or one split from it.
	*
	* @implNote This method is implemented to be equivalent to {@code
	* ints(Long.MAX_VALUE)}.
	*
	* @return a stream of pseudorandom {@code int} values
	*/
	public IntStream ints() {
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(this, 0L, Long.MAX_VALUE, Integer.MAX_VALUE, 0),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number
	* of pseudorandom {@code int} values from this generator and/or one split
	* from it; each value conforms to the given origin (inclusive) and bound
	* (exclusive).
	*
	* @param streamSize the number of values to generate
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code int} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero, or {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public IntStream ints(long streamSize, int randomNumberOrigin,
	int randomNumberBound) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* int} values from this generator and/or one split from it; each value
	* conforms to the given origin (inclusive) and bound (exclusive).
	*
	* @implNote This method is implemented to be equivalent to {@code
	* ints(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
	*
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code int} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public IntStream ints(int randomNumberOrigin, int randomNumberBound) {
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number
	* of pseudorandom {@code long} values from this generator and/or
	* one split from it.
	*
	* @param streamSize the number of values to generate
	* @return a stream of pseudorandom {@code long} values
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero
	*/
	public LongStream longs(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(this, 0L, streamSize, Long.MAX_VALUE, 0L),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* long} values from this generator and/or one split from it.
	*
	* @implNote This method is implemented to be equivalent to {@code
	* longs(Long.MAX_VALUE)}.
	*
	* @return a stream of pseudorandom {@code long} values
	*/
	public LongStream longs() {
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(this, 0L, Long.MAX_VALUE, Long.MAX_VALUE, 0L),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code long} values from this generator and/or one split
	* from it; each value conforms to the given origin (inclusive) and bound
	* (exclusive).
	*
	* @param streamSize the number of values to generate
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code long} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero, or {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public LongStream longs(long streamSize, long randomNumberOrigin,
	long randomNumberBound) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* long} values from this generator and/or one split from it; each value
	* conforms to the given origin (inclusive) and bound (exclusive).
	*
	* @implNote This method is implemented to be equivalent to {@code
	* longs(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
	*
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code long} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public LongStream longs(long randomNumberOrigin, long randomNumberBound) {
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code double} values from this generator and/or one split
	* from it; each value is between zero (inclusive) and one (exclusive).
	*
	* @param streamSize the number of values to generate
	* @return a stream of {@code double} values
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero
	*/
	public DoubleStream doubles(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(this, 0L, streamSize, Double.MAX_VALUE, 0.0),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* double} values from this generator and/or one split from it; each value
	* is between zero (inclusive) and one (exclusive).
	*
	* @implNote This method is implemented to be equivalent to {@code
	* doubles(Long.MAX_VALUE)}.
	*
	* @return a stream of pseudorandom {@code double} values
	*/
	public DoubleStream doubles() {
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(this, 0L, Long.MAX_VALUE, Double.MAX_VALUE, 0.0),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code double} values from this generator and/or one split
	* from it; each value conforms to the given origin (inclusive) and bound
	* (exclusive).
	*
	* @param streamSize the number of values to generate
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code double} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code streamSize} is
	* less than zero
	* @throws IllegalArgumentException if {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public DoubleStream doubles(long streamSize, double randomNumberOrigin,
	double randomNumberBound) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	if (!(randomNumberOrigin < randomNumberBound))
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* double} values from this generator and/or one split from it; each value
	* conforms to the given origin (inclusive) and bound (exclusive).
	*
	* @implNote This method is implemented to be equivalent to {@code
	* doubles(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
	*
	* @param randomNumberOrigin the origin (inclusive) of each random value
	* @param randomNumberBound the bound (exclusive) of each random value
	* @return a stream of pseudorandom {@code double} values,
	* each with the given origin (inclusive) and bound (exclusive)
	* @throws IllegalArgumentException if {@code randomNumberOrigin}
	* is greater than or equal to {@code randomNumberBound}
	*/
	public DoubleStream doubles(double randomNumberOrigin, double randomNumberBound) {
	if (!(randomNumberOrigin < randomNumberBound))
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Spliterator for int streams. We multiplex the four int
	* versions into one class by treating a bound less than origin as
	* unbounded, and also by treating "infinite" as equivalent to
	* Long.MAX_VALUE. For splits, it uses the standard divide-by-two
	* approach. The long and double versions of this class are
	* identical except for types.
	*/
	static final class RandomIntsSpliterator implements Spliterator.OfInt {
	final SplittableRandom rng;
	long index;
	final long fence;
	final int origin;
	final int bound;
	RandomIntsSpliterator(SplittableRandom rng, long index, long fence,
	int origin, int bound) {
	this.rng = rng; this.index = index; this.fence = fence;
	this.origin = origin; this.bound = bound;
	}

	public RandomIntsSpliterator trySplit() {
	long i = index, m = (i + fence) >>> 1;
	return (m <= i) ? null :
	new RandomIntsSpliterator(rng.split(), i, index = m, origin, bound);
	}

	public long estimateSize() {
	return fence - index;
	}

	public int characteristics() {
	return (Spliterator.SIZED \| Spliterator.SUBSIZED \|
	Spliterator.NONNULL \| Spliterator.IMMUTABLE);
	}

	public boolean tryAdvance(IntConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	consumer.accept(rng.internalNextInt(origin, bound));
	index = i + 1;
	return true;
	}
	return false;
	}

	public void forEachRemaining(IntConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	index = f;
	SplittableRandom r = rng;
	int o = origin, b = bound;
	do {
	consumer.accept(r.internalNextInt(o, b));
	} while (++i < f);
	}
	}
	}

	/**
	* Spliterator for long streams.
	*/
	static final class RandomLongsSpliterator implements Spliterator.OfLong {
	final SplittableRandom rng;
	long index;
	final long fence;
	final long origin;
	final long bound;
	RandomLongsSpliterator(SplittableRandom rng, long index, long fence,
	long origin, long bound) {
	this.rng = rng; this.index = index; this.fence = fence;
	this.origin = origin; this.bound = bound;
	}

	public RandomLongsSpliterator trySplit() {
	long i = index, m = (i + fence) >>> 1;
	return (m <= i) ? null :
	new RandomLongsSpliterator(rng.split(), i, index = m, origin, bound);
	}

	public long estimateSize() {
	return fence - index;
	}

	public int characteristics() {
	return (Spliterator.SIZED \| Spliterator.SUBSIZED \|
	Spliterator.NONNULL \| Spliterator.IMMUTABLE);
	}

	public boolean tryAdvance(LongConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	consumer.accept(rng.internalNextLong(origin, bound));
	index = i + 1;
	return true;
	}
	return false;
	}

	public void forEachRemaining(LongConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	index = f;
	SplittableRandom r = rng;
	long o = origin, b = bound;
	do {
	consumer.accept(r.internalNextLong(o, b));
	} while (++i < f);
	}
	}

	}

	/**
	* Spliterator for double streams.
	*/
	static final class RandomDoublesSpliterator implements Spliterator.OfDouble {
	final SplittableRandom rng;
	long index;
	final long fence;
	final double origin;
	final double bound;
	RandomDoublesSpliterator(SplittableRandom rng, long index, long fence,
	double origin, double bound) {
	this.rng = rng; this.index = index; this.fence = fence;
	this.origin = origin; this.bound = bound;
	}

	public RandomDoublesSpliterator trySplit() {
	long i = index, m = (i + fence) >>> 1;
	return (m <= i) ? null :
	new RandomDoublesSpliterator(rng.split(), i, index = m, origin, bound);
	}

	public long estimateSize() {
	return fence - index;
	}

	public int characteristics() {
	return (Spliterator.SIZED \| Spliterator.SUBSIZED \|
	Spliterator.NONNULL \| Spliterator.IMMUTABLE);
	}

	public boolean tryAdvance(DoubleConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	consumer.accept(rng.internalNextDouble(origin, bound));
	index = i + 1;
	return true;
	}
	return false;
	}

	public void forEachRemaining(DoubleConsumer consumer) {
	if (consumer == null) throw new NullPointerException();
	long i = index, f = fence;
	if (i < f) {
	index = f;
	SplittableRandom r = rng;
	double o = origin, b = bound;
	do {
	consumer.accept(r.internalNextDouble(o, b));
	} while (++i < f);
	}
	}
	}

	}

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