diff -r c660730af328 -r 214afc7a1e02 src/java.base/share/classes/java/util/SplittableRandom.java --- a/src/java.base/share/classes/java/util/SplittableRandom.java Thu Nov 14 12:36:46 2019 -0400 +++ b/src/java.base/share/classes/java/util/SplittableRandom.java Thu Nov 14 12:39:49 2019 -0400 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2013, 2019, 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 @@ -22,17 +22,13 @@ * or visit www.oracle.com if you need additional information or have any * questions. */ - package java.util; +import java.math.BigInteger; 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 java.util.random.RandomGenerator.SplittableGenerator; +import java.util.random.RandomSupport; +import java.util.random.RandomSupport.AbstractSplittableGenerator; /** * A generator of uniform pseudorandom values applicable for use in @@ -52,15 +48,15 @@ * types and ranges, but similar properties are expected to hold, at * least approximately, for others as well. The period * (length of any series of generated values before it repeats) is at - * least 2⁶⁴. + * least 2⁶⁴. * - *

Method {@link #split} constructs and returns a new + *

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. + * SplittableRandom} object.

* *

Instances of SplittableRandom are not thread-safe. * They are designed to be split, not shared, across threads. For @@ -71,7 +67,7 @@ * *

This class provides additional methods for generating random * streams, that employ the above techniques when used in {@code - * stream.parallel()} mode. + * stream.parallel()} mode.

* * * @@ -80,13 +76,13 @@ * in security-sensitive applications. Additionally, * default-constructed instances do not use a cryptographically random * seed unless the {@linkplain System#getProperty system property} - * {@systemProperty java.util.secureRandomSeed} is set to {@code true}. + * {@code java.util.secureRandomSeed} is set to {@code true}. * * @author Guy Steele * @author Doug Lea * @since 1.8 */ -public final class SplittableRandom { +public final class SplittableRandom extends AbstractSplittableGenerator { /* * Implementation Overview. @@ -161,12 +157,6 @@ 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; @@ -186,6 +176,7 @@ /** * Computes Stafford variant 13 of 64bit mix function. + * http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html */ private static long mix64(long z) { z = (z ^ (z >>> 30)) * 0xbf58476d1ce4e5b9L; @@ -195,6 +186,7 @@ /** * Returns the 32 high bits of Stafford variant 4 mix64 function as int. + * http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html */ private static int mix32(long z) { z = (z ^ (z >>> 33)) * 0x62a9d9ed799705f5L; @@ -203,6 +195,8 @@ /** * Returns the gamma value to use for a new split instance. + * Uses the 64bit mix function from MurmurHash3. + * https://github.com/aappleby/smhasher/wiki/MurmurHash3 */ private static long mixGamma(long z) { z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL; // MurmurHash3 mix constants @@ -219,141 +213,10 @@ return seed += gamma; } - // IllegalArgumentException messages - static final String BAD_BOUND = "bound must be positive"; - static final String BAD_RANGE = "bound must be greater than origin"; - static final String BAD_SIZE = "size must be non-negative"; - /** * The seed generator for default constructors. */ - private static final AtomicLong defaultGen - = new AtomicLong(mix64(System.currentTimeMillis()) ^ - mix64(System.nanoTime())); - - // at end of to survive static initialization circularity - static { - if (java.security.AccessController.doPrivileged( - new java.security.PrivilegedAction() { - public Boolean run() { - return Boolean.getBoolean("java.util.secureRandomSeed"); - }})) { - 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); - defaultGen.set(s); - } - } - - /* - * 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 (2⁶⁴) 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; - } + private static final AtomicLong defaultGen = new AtomicLong(RandomSupport.initialSeed()); /* ---------------- public methods ---------------- */ @@ -375,11 +238,13 @@ * may, and typically does, vary across program invocations. */ public SplittableRandom() { // emulate defaultGen.split() - long s = defaultGen.getAndAdd(GOLDEN_GAMMA << 1); + long s = defaultGen.getAndAdd(2 * GOLDEN_GAMMA); this.seed = mix64(s); this.gamma = mixGamma(s + GOLDEN_GAMMA); } + // public SplittableRandom copy() { return new SplittableRandom(seed, gamma); } + /** * Constructs and returns a new SplittableRandom instance that * shares no mutable state with this instance. However, with very @@ -398,24 +263,8 @@ return new SplittableRandom(nextLong(), mixGamma(nextSeed())); } - /** - * Fills a user-supplied byte array with generated pseudorandom bytes. - * - * @param bytes the byte array to fill with pseudorandom bytes - * @throws NullPointerException if bytes is null - * @since 10 - */ - public void nextBytes(byte[] bytes) { - int i = 0; - int len = bytes.length; - for (int words = len >> 3; words--> 0; ) { - long rnd = nextLong(); - for (int n = 8; n--> 0; rnd >>>= Byte.SIZE) - bytes[i++] = (byte)rnd; - } - if (i < len) - for (long rnd = nextLong(); i < len; rnd >>>= Byte.SIZE) - bytes[i++] = (byte)rnd; + public SplittableRandom split(SplittableGenerator source) { + return new SplittableRandom(source.nextLong(), mixGamma(source.nextLong())); } /** @@ -428,49 +277,6 @@ } /** - * 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(BAD_BOUND); - // 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(BAD_RANGE); - return internalNextInt(origin, bound); - } - - /** * Returns a pseudorandom {@code long} value. * * @return a pseudorandom {@code long} value @@ -479,537 +285,10 @@ 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(BAD_BOUND); - // 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(BAD_RANGE); - 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(BAD_BOUND); - 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(BAD_RANGE); - 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(BAD_SIZE); - 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(BAD_SIZE); - if (randomNumberOrigin >= randomNumberBound) - throw new IllegalArgumentException(BAD_RANGE); - 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(BAD_RANGE); - 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(BAD_SIZE); - 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(BAD_SIZE); - if (randomNumberOrigin >= randomNumberBound) - throw new IllegalArgumentException(BAD_RANGE); - return StreamSupport.longStream - (new RandomLongsSpliterator - (this, 0L, streamSize, randomNumberOrigin, randomNumberBound), - false); - } + static final BigInteger PERIOD = BigInteger.ONE.shiftLeft(64); // Period is 2**64 - /** - * 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(BAD_RANGE); - 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(BAD_SIZE); - 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, or {@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(BAD_SIZE); - if (!(randomNumberOrigin < randomNumberBound)) - throw new IllegalArgumentException(BAD_RANGE); - 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(BAD_RANGE); - 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. - */ - private 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. - */ - private 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. - */ - private 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); - } - } + public BigInteger period() { + return PERIOD; } }