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Comparing jsr166/src/main/java/util/SplittableRandom.java (file contents):
Revision 1.13 by dl, Thu Jul 25 13:19:09 2013 UTC vs.
Revision 1.18 by dl, Thu Aug 22 23:36:06 2013 UTC

#	Line 26 | Line 26
26		package java.util;
27
28		import java.security.SecureRandom;
29	+	import java.net.InetAddress;
30		import java.util.concurrent.atomic.AtomicLong;
30	–	import java.util.Spliterator;
31		import java.util.function.IntConsumer;
32		import java.util.function.LongConsumer;
33		import java.util.function.DoubleConsumer;
#	Line 39 | Line 39 | import java.util.stream.DoubleStream;
39		/**
40		* A generator of uniform pseudorandom values applicable for use in
41		* (among other contexts) isolated parallel computations that may
42	<	* generate subtasks. Class SplittableRandom supports methods for
42	>	* generate subtasks. Class {@code SplittableRandom} supports methods for
43		* producing pseudorandom numbers of type {@code int}, {@code long},
44		* and {@code double} with similar usages as for class
45		* {@link java.util.Random} but differs in the following ways:
#	Line 77 | Line 77 | import java.util.stream.DoubleStream;
77		*
78		* </ul>
79		*
80	+	* <p>Instances of {@code SplittableRandom} are not cryptographically
81	+	* secure.  Consider instead using {@link java.security.SecureRandom}
82	+	* in security-sensitive applications. Additionally,
83	+	* default-constructed instances do not use a cryptographically random
84	+	* seed unless the {@linkplain System#getProperty system property}
85	+	* {@code java.util.secureRandomSeed} is set to {@code true}.
86	+
87	+	*
88		* @author  Guy Steele
89		* @author  Doug Lea
90		* @since   1.8
#	Line 84 | Line 92 | import java.util.stream.DoubleStream;
92		public class SplittableRandom {
93
94		/*
87	–	* File organization: First the non-public methods that constitute
88	–	* the main algorithm, then the main public methods, followed by
89	–	* some custom spliterator classes needed for stream methods.
90	–	*
91	–	* Credits: Primary algorithm and code by Guy Steele.  Stream
92	–	* support methods by Doug Lea.  Documentation jointly produced
93	–	* with additional help from Brian Goetz.
94	–	*/
95	–
96	–	/*
95		* Implementation Overview.
96		*
97		* This algorithm was inspired by the "DotMix" algorithm by
98		* Leiserson, Schardl, and Sukha "Deterministic Parallel
99		* Random-Number Generation for Dynamic-Multithreading Platforms",
100	<	* PPoPP 2012, but improves and extends it in several ways.
101	<	*
102	<	* The primary update step (see method nextSeed()) is simply to
103	<	* add a constant ("gamma") to the current seed, modulo a prime
104	<	* ("George"). However, the nextLong and nextInt methods do not
105	<	* return this value, but instead the results of bit-mixing
106	<	* transformations that produce more uniformly distributed
107	<	* sequences.
108	<	*
109	<	* "George" is the otherwise nameless (because it cannot be
110	<	* represented) prime number 2^64+13. Using a prime number larger
111	<	* than can fit in a long ensures that all possible long values
112	<	* can occur, plus 13 others that just get skipped over when they
113	<	* are encountered; see method addGammaModGeorge. For this to
114	<	* work, initial gamma values must be at least 13.
117	<	*
118	<	* The mix64 bit-mixing function called by nextLong and other
119	<	* methods computes the same value as the "64-bit finalizer"
120	<	* function in Austin Appleby's MurmurHash3 algorithm.  See
100	>	* PPoPP 2012, as well as those in "Parallel random numbers: as
101	>	* easy as 1, 2, 3" by Salmon, Morae, Dror, and Shaw, SC 2011.  It
102	>	* differs mainly in simplifying and cheapening operations.
103	>	*
104	>	* The primary update step (method nextSeed()) is to add a
105	>	* constant ("gamma") to the current (64 bit) seed, forming a
106	>	* simple sequence.  The seed and the gamma values for any two
107	>	* SplittableRandom instances are highly likely to be different.
108	>	*
109	>	* Methods nextLong, nextInt, and derivatives do not return the
110	>	* sequence (seed) values, but instead a hash-like bit-mix of
111	>	* their bits, producing more independently distributed sequences.
112	>	* For nextLong, the mix64 bit-mixing function computes the same
113	>	* value as the "64-bit finalizer" function in Austin Appleby's
114	>	* MurmurHash3 algorithm.  See
115		* http://code.google.com/p/smhasher/wiki/MurmurHash3 , which
116		* comments: "The constants for the finalizers were generated by a
117		* simple simulated-annealing algorithm, and both avalanche all
118	<	* bits of 'h' to within 0.25% bias."
119	<	*
120	<	* The value of gamma differs for each instance across a series of
121	<	* splits, and is generated using an independent variant of the
122	<	* same algorithm, but operating across calls to split(), not
123	<	* calls to nextSeed(): Each instance carries the state of this
124	<	* generator as nextSplit. Gammas are treated as 57bit values,
125	<	* advancing by adding GAMMA_GAMMA mod GAMMA_PRIME, and bit-mixed
126	<	* with a 57-bit version of mix, using the "Mix01" multiplicative
127	<	* constants for MurmurHash3 described by David Stafford
128	<	* (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html).
129	<	* The value of GAMMA_GAMMA is arbitrary (except must be at least
130	<	* 13 and less than GAMMA_PRIME), but because it serves as the
131	<	* base of split sequences, should be subject to validation of
132	<	* consequent random number quality metrics.
118	>	* bits of 'h' to within 0.25% bias." The mix32 function is
119	>	* equivalent to (int)(mix64(seed) >>> 32), but faster because it
120	>	* omits a step that doesn't contribute to result.
121	>	*
122	>	* The split operation uses the current generator to form the seed
123	>	* and gamma for another SplittableRandom.  To conservatively
124	>	* avoid potential correlations between seed and value generation,
125	>	* gamma selection (method nextGamma) uses the "Mix13" constants
126	>	* for MurmurHash3 described by David Stafford
127	>	* (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html)
128	>	* To avoid potential weaknesses in bit-mixing transformations, we
129	>	* restrict gammas to odd values with at least 12 and no more than
130	>	* 52 bits set.  Rather than rejecting candidates with too few or
131	>	* too many bits set, method nextGamma flips some bits (which has
132	>	* the effect of mapping at most 4 to any given gamma value).
133	>	* This reduces the effective set of 64bit odd gamma values by
134	>	* about 2<sup>14</sup>, a very tiny percentage, and serves as an
135	>	* automated screening for sequence constant selection that is
136	>	* left as an empirical decision in some other hashing and crypto
137	>	* algorithms.
138	>	*
139	>	* The resulting generator thus transforms a sequence in which
140	>	* (typically) many bits change on each step, with an inexpensive
141	>	* mixer with good (but less than cryptographically secure)
142	>	* avalanching.
143	>	*
144	>	* The default (no-argument) constructor, in essence, invokes
145	>	* split() for a common "seeder" SplittableRandom.  Unlike other
146	>	* cases, this split must be performed in a thread-safe manner, so
147	>	* we use an AtomicLong to represent the seed rather than use an
148	>	* explicit SplittableRandom. To bootstrap the seeder, we start
149	>	* off using a seed based on current time and host unless the
150	>	* SecureRandomSeed property is set. This serves as a
151	>	* slimmed-down (and insecure) variant of SecureRandom that also
152	>	* avoids stalls that may occur when using /dev/random.
153	>	*
154	>	* It is a relatively simple matter to apply the basic design here
155	>	* to use 128 bit seeds. However, emulating 128bit arithmetic and
156	>	* carrying around twice the state add more overhead than appears
157	>	* warranted for current usages.
158		*
159	<	* The mix32 function used for nextInt just consists of two of the
160	<	* five lines of mix64; avalanche testing shows that the 64-bit
161	<	* result has its top 32 bits avalanched well, though not the
143	<	* bottom 32 bits.  DieHarder tests show that it is adequate for
144	<	* generating one random int from the 64-bit result of nextSeed.
145	<	*
146	<	* Support for the default (no-argument) constructor relies on an
147	<	* AtomicLong (defaultSeedGenerator) to help perform the
148	<	* equivalent of a split of a statically constructed
149	<	* SplittableRandom. Unlike other cases, this split must be
150	<	* performed in a thread-safe manner. We use
151	<	* AtomicLong.compareAndSet as the (typically) most efficient
152	<	* mechanism. To bootstrap, we start off using a SecureRandom
153	<	* initial default seed, and update using a fixed
154	<	* DEFAULT_SEED_GAMMA. The default constructor uses GAMMA_GAMMA,
155	<	* not 0, for its splitSeed argument (addGammaModGeorge(0,
156	<	* GAMMA_GAMMA) == GAMMA_GAMMA) to reflect that each is split from
157	<	* this root generator, even though the root is not explicitly
158	<	* represented as a SplittableRandom.
159	<	*/
160	<
161	<	/**
162	<	* The prime modulus for gamma values.
163	<	*/
164	<	private static final long GAMMA_PRIME = (1L << 57) - 13L;
165	<
166	<	/**
167	<	* The value for producing new gamma values. Must be greater or
168	<	* equal to 13 and less than GAMMA_PRIME. Otherwise, the value is
169	<	* arbitrary subject to validation of the resulting statistical
170	<	* quality of splits.
171	<	*/
172	<	private static final long GAMMA_GAMMA = 0x00aae38294f712aabL;
173	<
174	<	/**
175	<	* The seed update value for default constructors.  Must be
176	<	* greater or equal to 13. Otherwise, the value is arbitrary
177	<	* subject to quality checks.
159	>	* File organization: First the non-public methods that constitute
160	>	* the main algorithm, then the main public methods, followed by
161	>	* some custom spliterator classes needed for stream methods.
162		*/
179	–	private static final long DEFAULT_SEED_GAMMA = 0x9e3779b97f4a7c15L;
163
164		/**
165	<	* The value 13 with 64bit sign bit set. Used in the signed
166	<	* comparison in addGammaModGeorge.
165	>	* The initial gamma value for (unsplit) SplittableRandoms. Must
166	>	* be odd with at least 12 and no more than 52 bits set. Currently
167	>	* set to the golden ratio scaled to 64bits.
168		*/
169	<	private static final long BOTTOM13 = 0x800000000000000DL;
169	>	private static final long INITIAL_GAMMA = 0x9e3779b97f4a7c15L;
170
171		/**
172		* The least non-zero value returned by nextDouble(). This value
#	Line 191 | Line 175 | public class SplittableRandom {
175		private static final double DOUBLE_UNIT = 1.0 / (1L << 53);
176
177		/**
178	<	* The next seed for default constructors.
195	<	*/
196	<	private static final AtomicLong defaultSeedGenerator =
197	<	new AtomicLong(getInitialDefaultSeed());
198	<
199	<	/**
200	<	* The seed, updated only via method nextSeed.
178	>	* The seed. Updated only via method nextSeed.
179		*/
180		private long seed;
181
182		/**
183	<	* The constant value added to seed (mod George) on each update.
183	>	* The step value.
184		*/
185		private final long gamma;
186
187		/**
188	<	* The next seed to use for splits. Propagated using
211	<	* addGammaModGeorge across instances.
212	<	*/
213	<	private final long nextSplit;
214	<
215	<	/**
216	<	* Adds the given gamma value, g, to the given seed value s, mod
217	<	* George (2^64+13). We regard s and g as unsigned values
218	<	* (ranging from 0 to 2^64-1). We add g to s either once or twice
219	<	* (mod George) as necessary to produce an (unsigned) result less
220	<	* than 2^64.  We require that g must be at least 13. This
221	<	* guarantees that if (s+g) mod George >= 2^64 then (s+g+g) mod
222	<	* George < 2^64; thus we need only a conditional, not a loop,
223	<	* to be sure of getting a representable value.
224	<	*
225	<	* Because Java comparison operators are signed, we implement this
226	<	* by conceptually offsetting seed values downwards by 2^63, so
227	<	* 0..13 is represented as Long.MIN_VALUE..BOTTOM13.
228	<	*
229	<	* @param s a seed value, viewed as a signed long
230	<	* @param g a gamma value, 13 <= g (as unsigned)
188	>	* Internal constructor used by all others except default constructor.
189		*/
190	<	private static long addGammaModGeorge(long s, long g) {
191	<	long p = s + g;
192	<	return (p >= s) ? p : ((p >= BOTTOM13) ? p  : p + g) - 13L;
190	>	private SplittableRandom(long seed, long gamma) {
191	>	this.seed = seed;
192	>	this.gamma = gamma;
193		}
194
195		/**
196	<	* Returns a bit-mixed transformation of its argument.
239	<	* See above for explanation.
196	>	* Computes MurmurHash3 64bit mix function.
197		*/
198		private static long mix64(long z) {
199	<	z ^= (z >>> 33);
200	<	z *= 0xff51afd7ed558ccdL;
201	<	z ^= (z >>> 33);
245	<	z *= 0xc4ceb9fe1a85ec53L;
246	<	z ^= (z >>> 33);
247	<	return z;
199	>	z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
200	>	z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L;
201	>	return z ^ (z >>> 33);
202		}
203
204		/**
205	<	* Returns a bit-mixed int transformation of its argument.
252	<	* See above for explanation.
205	>	* Returns the 32 high bits of mix64(z) as int.
206		*/
207		private static int mix32(long z) {
208	<	z ^= (z >>> 33);
209	<	z *= 0xc4ceb9fe1a85ec53L;
257	<	return (int)(z >>> 32);
258	<	}
259	<
260	<	/**
261	<	* Returns a 57-bit mixed transformation of its argument.  See
262	<	* above for explanation.
263	<	*/
264	<	private static long mix57(long z) {
265	<	z ^= (z >>> 33);
266	<	z *= 0x7fb5d329728ea185L;
267	<	z &= 0x01FFFFFFFFFFFFFFL;
268	<	z ^= (z >>> 33);
269	<	z *= 0x81dadef4bc2dd44dL;
270	<	z &= 0x01FFFFFFFFFFFFFFL;
271	<	z ^= (z >>> 33);
272	<	return z;
208	>	z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
209	>	return (int)(((z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L) >>> 32);
210		}
211
212		/**
213	<	* Internal constructor used by all other constructors and by
277	<	* method split. Establishes the initial seed for this instance,
278	<	* and uses the given splitSeed to establish gamma, as well as the
279	<	* nextSplit to use by this instance. The loop to skip ineligible
280	<	* gammas very rarely iterates, and does so at most 13 times.
213	>	* Returns the gamma value to use for a new split instance.
214		*/
215	<	private SplittableRandom(long seed, long splitSeed) {
216	<	this.seed = seed;
217	<	long s = splitSeed, g;
218	<	do { // ensure gamma >= 13, considered as an unsigned integer
219	<	s += GAMMA_GAMMA;
220	<	if (s >= GAMMA_PRIME)
288	<	s -= GAMMA_PRIME;
289	<	g = mix57(s);
290	<	} while (g < 13L);
291	<	this.gamma = g;
292	<	this.nextSplit = s;
215	>	private static long nextGamma(long z) {
216	>	z = (z ^ (z >>> 30)) * 0xbf58476d1ce4e5b9L; // Stafford "Mix13"
217	>	z = (z ^ (z >>> 27)) * 0x94d049bb133111ebL;
218	>	z = (z ^ (z >>> 31)) | 1L; // force to be odd
219	>	int n = Long.bitCount(z);  // ensure enough 0 and 1 bits
220	>	return (n < 12 || n > 52) ? z ^ 0xaaaaaaaaaaaaaaaaL : z;
221		}
222
223		/**
224	<	* Updates in-place and returns seed.
297	<	* See above for explanation.
224	>	* Adds gamma to seed.
225		*/
226		private long nextSeed() {
227	<	return seed = addGammaModGeorge(seed, gamma);
227	>	return seed += gamma;
228		}
229
230		/**
231	<	* Atomically updates and returns next seed for default constructor.
231	>	* The seed generator for default constructors.
232		*/
233	<	private static long nextDefaultSeed() {
307	<	long oldSeed, newSeed;
308	<	do {
309	<	oldSeed = defaultSeedGenerator.get();
310	<	newSeed = addGammaModGeorge(oldSeed, DEFAULT_SEED_GAMMA);
311	<	} while (!defaultSeedGenerator.compareAndSet(oldSeed, newSeed));
312	<	return mix64(newSeed);
313	<	}
233	>	private static final AtomicLong seeder = new AtomicLong(initialSeed());
234
235	<	/**
236	<	* Returns an initial default seed.
237	<	*/
238	<	private static long getInitialDefaultSeed() {
239	<	byte[] seedBytes = java.security.SecureRandom.getSeed(8);
240	<	long s = (long)(seedBytes[0]) & 0xffL;
241	<	for (int i = 1; i < 8; ++i)
242	<	s = (s << 8) | ((long)(seedBytes[i]) & 0xffL);
243	<	return s;
235	>	private static long initialSeed() {
236	>	try {  // ignore exceptions in accessing/parsing properties
237	>	String pp = System.getProperty
238	>	("java.util.secureRandomSeed");
239	>	if (pp != null && pp.equalsIgnoreCase("true")) {
240	>	byte[] seedBytes = java.security.SecureRandom.getSeed(8);
241	>	long s = (long)(seedBytes[0]) & 0xffL;
242	>	for (int i = 1; i < 8; ++i)
243	>	s = (s << 8) | ((long)(seedBytes[i]) & 0xffL);
244	>	return s;
245	>	}
246	>	} catch (Exception ignore) {
247	>	}
248	>	int hh = 0; // hashed host address
249	>	try {
250	>	hh = InetAddress.getLocalHost().hashCode();
251	>	} catch (Exception ignore) {
252	>	}
253	>	return (mix64((((long)hh) << 32) ^ System.currentTimeMillis()) ^
254	>	mix64(System.nanoTime()));
255		}
256
257	+	// IllegalArgumentException messages
258	+	static final String BadBound = "bound must be positive";
259	+	static final String BadRange = "bound must be greater than origin";
260	+	static final String BadSize  = "size must be non-negative";
261	+
262		/*
263		* Internal versions of nextX methods used by streams, as well as
264		* the public nextX(origin, bound) methods.  These exist mainly to
#	Line 442 | Line 378 | public class SplittableRandom {
378		* @param seed the initial seed
379		*/
380		public SplittableRandom(long seed) {
381	<	this(seed, 0L);
381	>	this(seed, INITIAL_GAMMA);
382		}
383
384		/**
#	Line 451 | Line 387 | public class SplittableRandom {
387		* of those of any other instances in the current program; and
388		* may, and typically does, vary across program invocations.
389		*/
390	<	public SplittableRandom() {
391	<	this(nextDefaultSeed(), GAMMA_GAMMA);
390	>	public SplittableRandom() { // emulate seeder.split()
391	>	this.gamma = nextGamma(this.seed = seeder.addAndGet(INITIAL_GAMMA));
392		}
393
394		/**
#	Line 470 | Line 406 | public class SplittableRandom {
406		* @return the new SplittableRandom instance
407		*/
408		public SplittableRandom split() {
409	<	return new SplittableRandom(nextSeed(), nextSplit);
409	>	long s = nextSeed();
410	>	return new SplittableRandom(s, nextGamma(s));
411		}
412
413		/**
#	Line 486 | Line 423 | public class SplittableRandom {
423		* Returns a pseudorandom {@code int} value between zero (inclusive)
424		* and the specified bound (exclusive).
425		*
426	<	* @param bound the bound on the random number to be returned.  Must be
490	<	*        positive.
426	>	* @param bound the upper bound (exclusive).  Must be positive.
427		* @return a pseudorandom {@code int} value between zero
428		*         (inclusive) and the bound (exclusive)
429	<	* @throws IllegalArgumentException if the bound is less than zero
429	>	* @throws IllegalArgumentException if {@code bound} is not positive
430		*/
431		public int nextInt(int bound) {
432		if (bound <= 0)
433	<	throw new IllegalArgumentException("bound must be positive");
433	>	throw new IllegalArgumentException(BadBound);
434		// Specialize internalNextInt for origin 0
435		int r = mix32(nextSeed());
436		int m = bound - 1;
#	Line 522 | Line 458 | public class SplittableRandom {
458		*/
459		public int nextInt(int origin, int bound) {
460		if (origin >= bound)
461	<	throw new IllegalArgumentException("bound must be greater than origin");
461	>	throw new IllegalArgumentException(BadRange);
462		return internalNextInt(origin, bound);
463		}
464
#	Line 539 | Line 475 | public class SplittableRandom {
475		* Returns a pseudorandom {@code long} value between zero (inclusive)
476		* and the specified bound (exclusive).
477		*
478	<	* @param bound the bound on the random number to be returned.  Must be
543	<	*        positive.
478	>	* @param bound the upper bound (exclusive).  Must be positive.
479		* @return a pseudorandom {@code long} value between zero
480		*         (inclusive) and the bound (exclusive)
481	<	* @throws IllegalArgumentException if {@code bound} is less than zero
481	>	* @throws IllegalArgumentException if {@code bound} is not positive
482		*/
483		public long nextLong(long bound) {
484		if (bound <= 0)
485	<	throw new IllegalArgumentException("bound must be positive");
485	>	throw new IllegalArgumentException(BadBound);
486		// Specialize internalNextLong for origin 0
487		long r = mix64(nextSeed());
488		long m = bound - 1;
#	Line 575 | Line 510 | public class SplittableRandom {
510		*/
511		public long nextLong(long origin, long bound) {
512		if (origin >= bound)
513	<	throw new IllegalArgumentException("bound must be greater than origin");
513	>	throw new IllegalArgumentException(BadRange);
514		return internalNextLong(origin, bound);
515		}
516
#	Line 584 | Line 519 | public class SplittableRandom {
519		* (inclusive) and one (exclusive).
520		*
521		* @return a pseudorandom {@code double} value between zero
522	<	* (inclusive) and one (exclusive)
522	>	*         (inclusive) and one (exclusive)
523		*/
524		public double nextDouble() {
525		return (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT;
#	Line 594 | Line 529 | public class SplittableRandom {
529		* Returns a pseudorandom {@code double} value between 0.0
530		* (inclusive) and the specified bound (exclusive).
531		*
532	<	* @param bound the bound on the random number to be returned.  Must be
598	<	*        positive.
532	>	* @param bound the upper bound (exclusive).  Must be positive.
533		* @return a pseudorandom {@code double} value between zero
534		*         (inclusive) and the bound (exclusive)
535	<	* @throws IllegalArgumentException if {@code bound} is less than zero
535	>	* @throws IllegalArgumentException if {@code bound} is not positive
536		*/
537		public double nextDouble(double bound) {
538		if (!(bound > 0.0))
539	<	throw new IllegalArgumentException("bound must be positive");
539	>	throw new IllegalArgumentException(BadBound);
540		double result = (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT * bound;
541		return (result < bound) ?  result : // correct for rounding
542		Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1);
#	Line 613 | Line 547 | public class SplittableRandom {
547		* origin (inclusive) and bound (exclusive).
548		*
549		* @param origin the least value returned
550	<	* @param bound the upper bound
550	>	* @param bound the upper bound (exclusive)
551		* @return a pseudorandom {@code double} value between the origin
552		*         (inclusive) and the bound (exclusive)
553		* @throws IllegalArgumentException if {@code origin} is greater than
#	Line 621 | Line 555 | public class SplittableRandom {
555		*/
556		public double nextDouble(double origin, double bound) {
557		if (!(origin < bound))
558	<	throw new IllegalArgumentException("bound must be greater than origin");
558	>	throw new IllegalArgumentException(BadRange);
559		return internalNextDouble(origin, bound);
560		}
561
#	Line 638 | Line 572 | public class SplittableRandom {
572		// maintenance purposes the small differences across forms.
573
574		/**
575	<	* Returns a stream producing the given {@code streamSize} number of
576	<	* pseudorandom {@code int} values.
575	>	* Returns a stream producing the given {@code streamSize} number
576	>	* of pseudorandom {@code int} values from this generator and/or
577	>	* one split from it.
578		*
579		* @param streamSize the number of values to generate
580		* @return a stream of pseudorandom {@code int} values
#	Line 648 | Line 583 | public class SplittableRandom {
583		*/
584		public IntStream ints(long streamSize) {
585		if (streamSize < 0L)
586	<	throw new IllegalArgumentException("negative Stream size");
586	>	throw new IllegalArgumentException(BadSize);
587		return StreamSupport.intStream
588		(new RandomIntsSpliterator
589		(this, 0L, streamSize, Integer.MAX_VALUE, 0),
#	Line 657 | Line 592 | public class SplittableRandom {
592
593		/**
594		* Returns an effectively unlimited stream of pseudorandom {@code int}
595	<	* values.
595	>	* values from this generator and/or one split from it.
596		*
597		* @implNote This method is implemented to be equivalent to {@code
598		* ints(Long.MAX_VALUE)}.
#	Line 672 | Line 607 | public class SplittableRandom {
607		}
608
609		/**
610	<	* Returns a stream producing the given {@code streamSize} number of
611	<	* pseudorandom {@code int} values, each conforming to the given
612	<	* origin and bound.
610	>	* Returns a stream producing the given {@code streamSize} number
611	>	* of pseudorandom {@code int} values from this generator and/or one split
612	>	* from it; each value conforms to the given origin (inclusive) and bound
613	>	* (exclusive).
614		*
615		* @param streamSize the number of values to generate
616	<	* @param randomNumberOrigin the origin of each random value
617	<	* @param randomNumberBound the bound of each random value
616	>	* @param randomNumberOrigin the origin (inclusive) of each random value
617	>	* @param randomNumberBound the bound (exclusive) of each random value
618		* @return a stream of pseudorandom {@code int} values,
619	<	*         each with the given origin and bound
619	>	*         each with the given origin (inclusive) and bound (exclusive)
620		* @throws IllegalArgumentException if {@code streamSize} is
621		*         less than zero, or {@code randomNumberOrigin}
622		*         is greater than or equal to {@code randomNumberBound}
#	Line 688 | Line 624 | public class SplittableRandom {
624		public IntStream ints(long streamSize, int randomNumberOrigin,
625		int randomNumberBound) {
626		if (streamSize < 0L)
627	<	throw new IllegalArgumentException("negative Stream size");
627	>	throw new IllegalArgumentException(BadSize);
628		if (randomNumberOrigin >= randomNumberBound)
629	<	throw new IllegalArgumentException("bound must be greater than origin");
629	>	throw new IllegalArgumentException(BadRange);
630		return StreamSupport.intStream
631		(new RandomIntsSpliterator
632		(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
#	Line 699 | Line 635 | public class SplittableRandom {
635
636		/**
637		* Returns an effectively unlimited stream of pseudorandom {@code
638	<	* int} values, each conforming to the given origin and bound.
638	>	* int} values from this generator and/or one split from it; each value
639	>	* conforms to the given origin (inclusive) and bound (exclusive).
640		*
641		* @implNote This method is implemented to be equivalent to {@code
642		* ints(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
643		*
644	<	* @param randomNumberOrigin the origin of each random value
645	<	* @param randomNumberBound the bound of each random value
644	>	* @param randomNumberOrigin the origin (inclusive) of each random value
645	>	* @param randomNumberBound the bound (exclusive) of each random value
646		* @return a stream of pseudorandom {@code int} values,
647	<	*         each with the given origin and bound
647	>	*         each with the given origin (inclusive) and bound (exclusive)
648		* @throws IllegalArgumentException if {@code randomNumberOrigin}
649		*         is greater than or equal to {@code randomNumberBound}
650		*/
651		public IntStream ints(int randomNumberOrigin, int randomNumberBound) {
652		if (randomNumberOrigin >= randomNumberBound)
653	<	throw new IllegalArgumentException("bound must be greater than origin");
653	>	throw new IllegalArgumentException(BadRange);
654		return StreamSupport.intStream
655		(new RandomIntsSpliterator
656		(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
#	Line 721 | Line 658 | public class SplittableRandom {
658		}
659
660		/**
661	<	* Returns a stream producing the given {@code streamSize} number of
662	<	* pseudorandom {@code long} values.
661	>	* Returns a stream producing the given {@code streamSize} number
662	>	* of pseudorandom {@code long} values from this generator and/or
663	>	* one split from it.
664		*
665		* @param streamSize the number of values to generate
666		* @return a stream of pseudorandom {@code long} values
#	Line 731 | Line 669 | public class SplittableRandom {
669		*/
670		public LongStream longs(long streamSize) {
671		if (streamSize < 0L)
672	<	throw new IllegalArgumentException("negative Stream size");
672	>	throw new IllegalArgumentException(BadSize);
673		return StreamSupport.longStream
674		(new RandomLongsSpliterator
675		(this, 0L, streamSize, Long.MAX_VALUE, 0L),
#	Line 739 | Line 677 | public class SplittableRandom {
677		}
678
679		/**
680	<	* Returns an effectively unlimited stream of pseudorandom {@code long}
681	<	* values.
680	>	* Returns an effectively unlimited stream of pseudorandom {@code
681	>	* long} values from this generator and/or one split from it.
682		*
683		* @implNote This method is implemented to be equivalent to {@code
684		* longs(Long.MAX_VALUE)}.
#	Line 756 | Line 694 | public class SplittableRandom {
694
695		/**
696		* Returns a stream producing the given {@code streamSize} number of
697	<	* pseudorandom {@code long} values, each conforming to the
698	<	* given origin and bound.
697	>	* pseudorandom {@code long} values from this generator and/or one split
698	>	* from it; each value conforms to the given origin (inclusive) and bound
699	>	* (exclusive).
700		*
701		* @param streamSize the number of values to generate
702	<	* @param randomNumberOrigin the origin of each random value
703	<	* @param randomNumberBound the bound of each random value
702	>	* @param randomNumberOrigin the origin (inclusive) of each random value
703	>	* @param randomNumberBound the bound (exclusive) of each random value
704		* @return a stream of pseudorandom {@code long} values,
705	<	*         each with the given origin and bound
705	>	*         each with the given origin (inclusive) and bound (exclusive)
706		* @throws IllegalArgumentException if {@code streamSize} is
707		*         less than zero, or {@code randomNumberOrigin}
708		*         is greater than or equal to {@code randomNumberBound}
#	Line 771 | Line 710 | public class SplittableRandom {
710		public LongStream longs(long streamSize, long randomNumberOrigin,
711		long randomNumberBound) {
712		if (streamSize < 0L)
713	<	throw new IllegalArgumentException("negative Stream size");
713	>	throw new IllegalArgumentException(BadSize);
714		if (randomNumberOrigin >= randomNumberBound)
715	<	throw new IllegalArgumentException("bound must be greater than origin");
715	>	throw new IllegalArgumentException(BadRange);
716		return StreamSupport.longStream
717		(new RandomLongsSpliterator
718		(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
#	Line 782 | Line 721 | public class SplittableRandom {
721
722		/**
723		* Returns an effectively unlimited stream of pseudorandom {@code
724	<	* long} values, each conforming to the given origin and bound.
724	>	* long} values from this generator and/or one split from it; each value
725	>	* conforms to the given origin (inclusive) and bound (exclusive).
726		*
727		* @implNote This method is implemented to be equivalent to {@code
728		* longs(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
729		*
730	<	* @param randomNumberOrigin the origin of each random value
731	<	* @param randomNumberBound the bound of each random value
730	>	* @param randomNumberOrigin the origin (inclusive) of each random value
731	>	* @param randomNumberBound the bound (exclusive) of each random value
732		* @return a stream of pseudorandom {@code long} values,
733	<	*         each with the given origin and bound
733	>	*         each with the given origin (inclusive) and bound (exclusive)
734		* @throws IllegalArgumentException if {@code randomNumberOrigin}
735		*         is greater than or equal to {@code randomNumberBound}
736		*/
737		public LongStream longs(long randomNumberOrigin, long randomNumberBound) {
738		if (randomNumberOrigin >= randomNumberBound)
739	<	throw new IllegalArgumentException("bound must be greater than origin");
739	>	throw new IllegalArgumentException(BadRange);
740		return StreamSupport.longStream
741		(new RandomLongsSpliterator
742		(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
#	Line 805 | Line 745 | public class SplittableRandom {
745
746		/**
747		* Returns a stream producing the given {@code streamSize} number of
748	<	* pseudorandom {@code double} values, each between zero
749	<	* (inclusive) and one (exclusive).
748	>	* pseudorandom {@code double} values from this generator and/or one split
749	>	* from it; each value is between zero (inclusive) and one (exclusive).
750		*
751		* @param streamSize the number of values to generate
752		* @return a stream of {@code double} values
#	Line 815 | Line 755 | public class SplittableRandom {
755		*/
756		public DoubleStream doubles(long streamSize) {
757		if (streamSize < 0L)
758	<	throw new IllegalArgumentException("negative Stream size");
758	>	throw new IllegalArgumentException(BadSize);
759		return StreamSupport.doubleStream
760		(new RandomDoublesSpliterator
761		(this, 0L, streamSize, Double.MAX_VALUE, 0.0),
#	Line 824 | Line 764 | public class SplittableRandom {
764
765		/**
766		* Returns an effectively unlimited stream of pseudorandom {@code
767	<	* double} values, each between zero (inclusive) and one
768	<	* (exclusive).
767	>	* double} values from this generator and/or one split from it; each value
768	>	* is between zero (inclusive) and one (exclusive).
769		*
770		* @implNote This method is implemented to be equivalent to {@code
771		* doubles(Long.MAX_VALUE)}.
#	Line 841 | Line 781 | public class SplittableRandom {
781
782		/**
783		* Returns a stream producing the given {@code streamSize} number of
784	<	* pseudorandom {@code double} values, each conforming to the
785	<	* given origin and bound.
784	>	* pseudorandom {@code double} values from this generator and/or one split
785	>	* from it; each value conforms to the given origin (inclusive) and bound
786	>	* (exclusive).
787		*
788		* @param streamSize the number of values to generate
789	<	* @param randomNumberOrigin the origin of each random value
790	<	* @param randomNumberBound the bound of each random value
789	>	* @param randomNumberOrigin the origin (inclusive) of each random value
790	>	* @param randomNumberBound the bound (exclusive) of each random value
791		* @return a stream of pseudorandom {@code double} values,
792	<	* each with the given origin and bound
792	>	*         each with the given origin (inclusive) and bound (exclusive)
793		* @throws IllegalArgumentException if {@code streamSize} is
794	<	* less than zero
794	>	*         less than zero
795		* @throws IllegalArgumentException if {@code randomNumberOrigin}
796		*         is greater than or equal to {@code randomNumberBound}
797		*/
798		public DoubleStream doubles(long streamSize, double randomNumberOrigin,
799		double randomNumberBound) {
800		if (streamSize < 0L)
801	<	throw new IllegalArgumentException("negative Stream size");
801	>	throw new IllegalArgumentException(BadSize);
802		if (!(randomNumberOrigin < randomNumberBound))
803	<	throw new IllegalArgumentException("bound must be greater than origin");
803	>	throw new IllegalArgumentException(BadRange);
804		return StreamSupport.doubleStream
805		(new RandomDoublesSpliterator
806		(this, 0L, streamSize, randomNumberOrigin, randomNumberBound),
#	Line 868 | Line 809 | public class SplittableRandom {
809
810		/**
811		* Returns an effectively unlimited stream of pseudorandom {@code
812	<	* double} values, each conforming to the given origin and bound.
812	>	* double} values from this generator and/or one split from it; each value
813	>	* conforms to the given origin (inclusive) and bound (exclusive).
814		*
815		* @implNote This method is implemented to be equivalent to {@code
816		* doubles(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
817		*
818	<	* @param randomNumberOrigin the origin of each random value
819	<	* @param randomNumberBound the bound of each random value
818	>	* @param randomNumberOrigin the origin (inclusive) of each random value
819	>	* @param randomNumberBound the bound (exclusive) of each random value
820		* @return a stream of pseudorandom {@code double} values,
821	<	* each with the given origin and bound
821	>	*         each with the given origin (inclusive) and bound (exclusive)
822		* @throws IllegalArgumentException if {@code randomNumberOrigin}
823		*         is greater than or equal to {@code randomNumberBound}
824		*/
825		public DoubleStream doubles(double randomNumberOrigin, double randomNumberBound) {
826		if (!(randomNumberOrigin < randomNumberBound))
827	<	throw new IllegalArgumentException("bound must be greater than origin");
827	>	throw new IllegalArgumentException(BadRange);
828		return StreamSupport.doubleStream
829		(new RandomDoublesSpliterator
830		(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound),
#	Line 940 | Line 882 | public class SplittableRandom {
882		long i = index, f = fence;
883		if (i < f) {
884		index = f;
885	+	SplittableRandom r = rng;
886		int o = origin, b = bound;
887		do {
888	<	consumer.accept(rng.internalNextInt(o, b));
888	>	consumer.accept(r.internalNextInt(o, b));
889		} while (++i < f);
890		}
891		}
#	Line 994 | Line 937 | public class SplittableRandom {
937		long i = index, f = fence;
938		if (i < f) {
939		index = f;
940	+	SplittableRandom r = rng;
941		long o = origin, b = bound;
942		do {
943	<	consumer.accept(rng.internalNextLong(o, b));
943	>	consumer.accept(r.internalNextLong(o, b));
944		} while (++i < f);
945		}
946		}
#	Line 1049 | Line 993 | public class SplittableRandom {
993		long i = index, f = fence;
994		if (i < f) {
995		index = f;
996	+	SplittableRandom r = rng;
997		double o = origin, b = bound;
998		do {
999	<	consumer.accept(rng.internalNextDouble(o, b));
999	>	consumer.accept(r.internalNextDouble(o, b));
1000		} while (++i < f);
1001		}
1002		}

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