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	/*
	* 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.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* Written by Doug Lea with assistance from members of JCP JSR-166
	* Expert Group and released to the public domain, as explained at
	* http://creativecommons.org/publicdomain/zero/1.0/
	*/

	package java.util.concurrent;

	import java.io.ObjectStreamField;
	import java.util.Random;
	import java.util.Spliterator;
	import java.util.concurrent.atomic.AtomicInteger;
	import java.util.concurrent.atomic.AtomicLong;
	import java.util.function.DoubleConsumer;
	import java.util.function.IntConsumer;
	import java.util.function.LongConsumer;
	import java.util.stream.DoubleStream;
	import java.util.stream.IntStream;
	import java.util.stream.LongStream;
	import java.util.stream.StreamSupport;
	import sun.misc.VM;

	/**
	* A random number generator isolated to the current thread. Like the
	* global {@link java.util.Random} generator used by the {@link
	* java.lang.Math} class, a {@code ThreadLocalRandom} is initialized
	* with an internally generated seed that may not otherwise be
	* modified. When applicable, use of {@code ThreadLocalRandom} rather
	* than shared {@code Random} objects in concurrent programs will
	* typically encounter much less overhead and contention. Use of
	* {@code ThreadLocalRandom} is particularly appropriate when multiple
	* tasks (for example, each a {@link ForkJoinTask}) use random numbers
	* in parallel in thread pools.
	*
	* <p>Usages of this class should typically be of the form:
	* {@code ThreadLocalRandom.current().nextX(...)} (where
	* {@code X} is {@code Int}, {@code Long}, etc).
	* When all usages are of this form, it is never possible to
	* accidently share a {@code ThreadLocalRandom} across multiple threads.
	*
	* <p>This class also provides additional commonly used bounded random
	* generation methods.
	*
	* <p>Instances of {@code ThreadLocalRandom} 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}.
	*
	* @since 1.7
	* @author Doug Lea
	*/
	public class ThreadLocalRandom extends Random {
	/*
	* This class implements the java.util.Random API (and subclasses
	* Random) using a single static instance that accesses random
	* number state held in class Thread (primarily, field
	* threadLocalRandomSeed). In doing so, it also provides a home
	* for managing package-private utilities that rely on exactly the
	* same state as needed to maintain the ThreadLocalRandom
	* instances. We leverage the need for an initialization flag
	* field to also use it as a "probe" -- a self-adjusting thread
	* hash used for contention avoidance, as well as a secondary
	* simpler (xorShift) random seed that is conservatively used to
	* avoid otherwise surprising users by hijacking the
	* ThreadLocalRandom sequence. The dual use is a marriage of
	* convenience, but is a simple and efficient way of reducing
	* application-level overhead and footprint of most concurrent
	* programs.
	*
	* Even though this class subclasses java.util.Random, it uses the
	* same basic algorithm as java.util.SplittableRandom. (See its
	* internal documentation for explanations, which are not repeated
	* here.) Because ThreadLocalRandoms are not splittable
	* though, we use only a single 64bit gamma.
	*
	* Because this class is in a different package than class Thread,
	* field access methods use Unsafe to bypass access control rules.
	* To conform to the requirements of the Random superclass
	* constructor, the common static ThreadLocalRandom maintains an
	* "initialized" field for the sake of rejecting user calls to
	* setSeed while still allowing a call from constructor. Note
	* that serialization is completely unnecessary because there is
	* only a static singleton. But we generate a serial form
	* containing "rnd" and "initialized" fields to ensure
	* compatibility across versions.
	*
	* Implementations of non-core methods are mostly the same as in
	* SplittableRandom, that were in part derived from a previous
	* version of this class.
	*
	* The nextLocalGaussian ThreadLocal supports the very rarely used
	* nextGaussian method by providing a holder for the second of a
	* pair of them. As is true for the base class version of this
	* method, this time/space tradeoff is probably never worthwhile,
	* but we provide identical statistical properties.
	*/

	/** Generates per-thread initialization/probe field */
	private static final AtomicInteger probeGenerator =
	new AtomicInteger();

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

	private static long initialSeed() {
	String sec = VM.getSavedProperty("java.util.secureRandomSeed");
	if (Boolean.parseBoolean(sec)) {
	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()));
	}

	/**
	* The seed increment
	*/
	private static final long GAMMA = 0x9e3779b97f4a7c15L;

	/**
	* The increment for generating probe values
	*/
	private static final int PROBE_INCREMENT = 0x9e3779b9;

	/**
	* The increment of seeder per new instance
	*/
	private static final long SEEDER_INCREMENT = 0xbb67ae8584caa73bL;

	// Constants from SplittableRandom
	private static final double DOUBLE_UNIT = 0x1.0p-53; // 1.0 / (1L << 53)
	private static final float FLOAT_UNIT = 0x1.0p-24f; // 1.0f / (1 << 24)

	/** Rarely-used holder for the second of a pair of Gaussians */
	private static final ThreadLocal<Double> nextLocalGaussian =
	new ThreadLocal<Double>();

	private static long mix64(long z) {
	z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
	z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L;
	return z ^ (z >>> 33);
	}

	private static int mix32(long z) {
	z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
	return (int)(((z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L) >>> 32);
	}

	/**
	* Field used only during singleton initialization.
	* True when constructor completes.
	*/
	boolean initialized;

	/** Constructor used only for static singleton */
	private ThreadLocalRandom() {
	initialized = true; // false during super() call
	}

	/** The common ThreadLocalRandom */
	static final ThreadLocalRandom instance = new ThreadLocalRandom();

	/**
	* Initialize Thread fields for the current thread. Called only
	* when Thread.threadLocalRandomProbe is zero, indicating that a
	* thread local seed value needs to be generated. Note that even
	* though the initialization is purely thread-local, we need to
	* rely on (static) atomic generators to initialize the values.
	*/
	static final void localInit() {
	int p = probeGenerator.addAndGet(PROBE_INCREMENT);
	int probe = (p == 0) ? 1 : p; // skip 0
	long seed = mix64(seeder.getAndAdd(SEEDER_INCREMENT));
	Thread t = Thread.currentThread();
	UNSAFE.putLong(t, SEED, seed);
	UNSAFE.putInt(t, PROBE, probe);
	}

	/**
	* Returns the current thread's {@code ThreadLocalRandom}.
	*
	* @return the current thread's {@code ThreadLocalRandom}
	*/
	public static ThreadLocalRandom current() {
	if (UNSAFE.getInt(Thread.currentThread(), PROBE) == 0)
	localInit();
	return instance;
	}

	/**
	* Throws {@code UnsupportedOperationException}. Setting seeds in
	* this generator is not supported.
	*
	* @throws UnsupportedOperationException always
	*/
	public void setSeed(long seed) {
	// only allow call from super() constructor
	if (initialized)
	throw new UnsupportedOperationException();
	}

	final long nextSeed() {
	Thread t; long r; // read and update per-thread seed
	UNSAFE.putLong(t = Thread.currentThread(), SEED,
	r = UNSAFE.getLong(t, SEED) + GAMMA);
	return r;
	}

	// We must define this, but never use it.
	protected int next(int bits) {
	return (int)(mix64(nextSeed()) >>> (64 - bits));
	}

	// 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";

	/**
	* 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) {
	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;
	}

	/**
	* 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);
	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);
	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;
	}

	/**
	* Returns a pseudorandom {@code float} value between zero
	* (inclusive) and one (exclusive).
	*
	* @return a pseudorandom {@code float} value between zero
	* (inclusive) and one (exclusive)
	*/
	public float nextFloat() {
	return (mix32(nextSeed()) >>> 8) * FLOAT_UNIT;
	}

	public double nextGaussian() {
	// Use nextLocalGaussian instead of nextGaussian field
	Double d = nextLocalGaussian.get();
	if (d != null) {
	nextLocalGaussian.set(null);
	return d.doubleValue();
	}
	double v1, v2, s;
	do {
	v1 = 2 * nextDouble() - 1; // between -1 and 1
	v2 = 2 * nextDouble() - 1; // between -1 and 1
	s = v1 * v1 + v2 * v2;
	} while (s >= 1 \|\| s == 0);
	double multiplier = StrictMath.sqrt(-2 * StrictMath.log(s)/s);
	nextLocalGaussian.set(new Double(v2 * multiplier));
	return v1 * multiplier;
	}

	// 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.
	*
	* @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
	* @since 1.8
	*/
	public IntStream ints(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(0L, streamSize, Integer.MAX_VALUE, 0),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code int}
	* values.
	*
	* @implNote This method is implemented to be equivalent to {@code
	* ints(Long.MAX_VALUE)}.
	*
	* @return a stream of pseudorandom {@code int} values
	* @since 1.8
	*/
	public IntStream ints() {
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(0L, Long.MAX_VALUE, Integer.MAX_VALUE, 0),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number
	* of pseudorandom {@code int} values, each conforming 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}
	* @since 1.8
	*/
	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
	(0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* int} values, each conforming 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}
	* @since 1.8
	*/
	public IntStream ints(int randomNumberOrigin, int randomNumberBound) {
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.intStream
	(new RandomIntsSpliterator
	(0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code long} values.
	*
	* @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
	* @since 1.8
	*/
	public LongStream longs(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(0L, streamSize, Long.MAX_VALUE, 0L),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code long}
	* values.
	*
	* @implNote This method is implemented to be equivalent to {@code
	* longs(Long.MAX_VALUE)}.
	*
	* @return a stream of pseudorandom {@code long} values
	* @since 1.8
	*/
	public LongStream longs() {
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(0L, Long.MAX_VALUE, Long.MAX_VALUE, 0L),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code long}, each conforming 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}
	* @since 1.8
	*/
	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
	(0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* long} values, each conforming 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}
	* @since 1.8
	*/
	public LongStream longs(long randomNumberOrigin, long randomNumberBound) {
	if (randomNumberOrigin >= randomNumberBound)
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.longStream
	(new RandomLongsSpliterator
	(0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code double} values, each 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
	* @since 1.8
	*/
	public DoubleStream doubles(long streamSize) {
	if (streamSize < 0L)
	throw new IllegalArgumentException(BadSize);
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(0L, streamSize, Double.MAX_VALUE, 0.0),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* double} values, each 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
	* @since 1.8
	*/
	public DoubleStream doubles() {
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(0L, Long.MAX_VALUE, Double.MAX_VALUE, 0.0),
	false);
	}

	/**
	* Returns a stream producing the given {@code streamSize} number of
	* pseudorandom {@code double} values, each conforming 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}
	* @since 1.8
	*/
	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
	(0L, streamSize, randomNumberOrigin, randomNumberBound),
	false);
	}

	/**
	* Returns an effectively unlimited stream of pseudorandom {@code
	* double} values, each conforming 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}
	* @since 1.8
	*/
	public DoubleStream doubles(double randomNumberOrigin, double randomNumberBound) {
	if (!(randomNumberOrigin < randomNumberBound))
	throw new IllegalArgumentException(BadRange);
	return StreamSupport.doubleStream
	(new RandomDoublesSpliterator
	(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 {
	long index;
	final long fence;
	final int origin;
	final int bound;
	RandomIntsSpliterator(long index, long fence,
	int origin, int bound) {
	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(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(ThreadLocalRandom.current().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;
	int o = origin, b = bound;
	ThreadLocalRandom rng = ThreadLocalRandom.current();
	do {
	consumer.accept(rng.internalNextInt(o, b));
	} while (++i < f);
	}
	}
	}

	/**
	* Spliterator for long streams.
	*/
	static final class RandomLongsSpliterator implements Spliterator.OfLong {
	long index;
	final long fence;
	final long origin;
	final long bound;
	RandomLongsSpliterator(long index, long fence,
	long origin, long bound) {
	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(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(ThreadLocalRandom.current().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;
	long o = origin, b = bound;
	ThreadLocalRandom rng = ThreadLocalRandom.current();
	do {
	consumer.accept(rng.internalNextLong(o, b));
	} while (++i < f);
	}
	}

	}

	/**
	* Spliterator for double streams.
	*/
	static final class RandomDoublesSpliterator implements Spliterator.OfDouble {
	long index;
	final long fence;
	final double origin;
	final double bound;
	RandomDoublesSpliterator(long index, long fence,
	double origin, double bound) {
	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(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(ThreadLocalRandom.current().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;
	double o = origin, b = bound;
	ThreadLocalRandom rng = ThreadLocalRandom.current();
	do {
	consumer.accept(rng.internalNextDouble(o, b));
	} while (++i < f);
	}
	}
	}


	// Within-package utilities

	/*
	* Descriptions of the usages of the methods below can be found in
	* the classes that use them. Briefly, a thread's "probe" value is
	* a non-zero hash code that (probably) does not collide with
	* other existing threads with respect to any power of two
	* collision space. When it does collide, it is pseudo-randomly
	* adjusted (using a Marsaglia XorShift). The nextSecondarySeed
	* method is used in the same contexts as ThreadLocalRandom, but
	* only for transient usages such as random adaptive spin/block
	* sequences for which a cheap RNG suffices and for which it could
	* in principle disrupt user-visible statistical properties of the
	* main ThreadLocalRandom if we were to use it.
	*
	* Note: Because of package-protection issues, versions of some
	* these methods also appear in some subpackage classes.
	*/

	/**
	* Returns the probe value for the current thread without forcing
	* initialization. Note that invoking ThreadLocalRandom.current()
	* can be used to force initialization on zero return.
	*/
	static final int getProbe() {
	return UNSAFE.getInt(Thread.currentThread(), PROBE);
	}

	/**
	* Pseudo-randomly advances and records the given probe value for the
	* given thread.
	*/
	static final int advanceProbe(int probe) {
	probe ^= probe << 13; // xorshift
	probe ^= probe >>> 17;
	probe ^= probe << 5;
	UNSAFE.putInt(Thread.currentThread(), PROBE, probe);
	return probe;
	}

	/**
	* Returns the pseudo-randomly initialized or updated secondary seed.
	*/
	static final int nextSecondarySeed() {
	int r;
	Thread t = Thread.currentThread();
	if ((r = UNSAFE.getInt(t, SECONDARY)) != 0) {
	r ^= r << 13; // xorshift
	r ^= r >>> 17;
	r ^= r << 5;
	}
	else {
	localInit();
	if ((r = (int)UNSAFE.getLong(t, SEED)) == 0)
	r = 1; // avoid zero
	}
	UNSAFE.putInt(t, SECONDARY, r);
	return r;
	}

	// Serialization support

	private static final long serialVersionUID = -5851777807851030925L;

	/**
	* @serialField rnd long
	* seed for random computations
	* @serialField initialized boolean
	* always true
	*/
	private static final ObjectStreamField[] serialPersistentFields = {
	new ObjectStreamField("rnd", long.class),
	new ObjectStreamField("initialized", boolean.class),
	};

	/**
	* Saves the {@code ThreadLocalRandom} to a stream (that is, serializes it).
	* @param s the stream
	* @throws java.io.IOException if an I/O error occurs
	*/
	private void writeObject(java.io.ObjectOutputStream s)
	throws java.io.IOException {

	java.io.ObjectOutputStream.PutField fields = s.putFields();
	fields.put("rnd", UNSAFE.getLong(Thread.currentThread(), SEED));
	fields.put("initialized", true);
	s.writeFields();
	}

	/**
	* Returns the {@link #current() current} thread's {@code ThreadLocalRandom}.
	* @return the {@link #current() current} thread's {@code ThreadLocalRandom}
	*/
	private Object readResolve() {
	return current();
	}

	// Unsafe mechanics
	private static final sun.misc.Unsafe UNSAFE;
	private static final long SEED;
	private static final long PROBE;
	private static final long SECONDARY;
	static {
	try {
	UNSAFE = sun.misc.Unsafe.getUnsafe();
	Class<?> tk = Thread.class;
	SEED = UNSAFE.objectFieldOffset
	(tk.getDeclaredField("threadLocalRandomSeed"));
	PROBE = UNSAFE.objectFieldOffset
	(tk.getDeclaredField("threadLocalRandomProbe"));
	SECONDARY = UNSAFE.objectFieldOffset
	(tk.getDeclaredField("threadLocalRandomSecondarySeed"));
	} catch (Exception e) {
	throw new Error(e);
	}
	}
	}

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