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Comparing jsr166/src/main/java/util/SplittableRandom.java (file contents):
Revision 1.15 by dl, Fri Aug 9 12:12:10 2013 UTC vs.
Revision 1.21 by dl, Thu Sep 19 23:19:43 2013 UTC

# Line 25 | Line 25
25  
26   package java.util;
27  
28 < import java.net.InetAddress;
28 > import java.security.SecureRandom;
29 > import java.net.NetworkInterface;
30 > import java.util.Enumeration;
31   import java.util.concurrent.atomic.AtomicLong;
30 import java.util.Spliterator;
32   import java.util.function.IntConsumer;
33   import java.util.function.LongConsumer;
34   import java.util.function.DoubleConsumer;
# Line 39 | Line 40 | import java.util.stream.DoubleStream;
40   /**
41   * A generator of uniform pseudorandom values applicable for use in
42   * (among other contexts) isolated parallel computations that may
43 < * generate subtasks. Class SplittableRandom supports methods for
43 > * generate subtasks. Class {@code SplittableRandom} supports methods for
44   * producing pseudorandom numbers of type {@code int}, {@code long},
45   * and {@code double} with similar usages as for class
46   * {@link java.util.Random} but differs in the following ways:
# Line 77 | Line 78 | import java.util.stream.DoubleStream;
78   *
79   * </ul>
80   *
81 + * <p>Instances of {@code SplittableRandom} are not cryptographically
82 + * secure.  Consider instead using {@link java.security.SecureRandom}
83 + * in security-sensitive applications. Additionally,
84 + * default-constructed instances do not use a cryptographically random
85 + * seed unless the {@linkplain System#getProperty system property}
86 + * {@code java.util.secureRandomSeed} is set to {@code true}.
87 + *
88   * @author  Guy Steele
89   * @author  Doug Lea
90   * @since   1.8
# Line 101 | Line 109 | public class SplittableRandom {
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." The mix32 function is
111 <     * equivalent to (int)(mix64(seed) >>> 32), but faster because it
112 <     * omits a step that doesn't contribute to result.
112 >     * For nextLong, the mix64 function is based on David Stafford's
113 >     * (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html)
114 >     * "Mix13" variant of the "64-bit finalizer" function in Austin
115 >     * Appleby's MurmurHash3 algorithm See
116 >     * http://code.google.com/p/smhasher/wiki/MurmurHash3 . The mix32
117 >     * function is based on Stafford's Mix04 mix function, but returns
118 >     * the upper 32 bits cast as int.
119       *
120       * The split operation uses the current generator to form the seed
121       * and gamma for another SplittableRandom.  To conservatively
122       * avoid potential correlations between seed and value generation,
123 <     * gamma selection (method nextGamma) uses the "Mix13" constants
124 <     * for MurmurHash3 described by David Stafford
125 <     * (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html)
126 <     * To avoid potential weaknesses in bit-mixing transformations, we
127 <     * restrict gammas to odd values with at least 12 and no more than
128 <     * 52 bits set.  Rather than rejecting candidates with too few or
129 <     * too many bits set, method nextGamma flips some bits (which has
130 <     * the effect of mapping at most 4 to any given gamma value).
125 <     * This reduces the effective set of 64bit odd gamma values by
126 <     * about 2<sup>14</sup>, a very tiny percentage, and serves as an
123 >     * gamma selection (method mixGamma) uses different
124 >     * (Murmurhash3's) mix constants.  To avoid potential weaknesses
125 >     * in bit-mixing transformations, we restrict gammas to odd values
126 >     * with at least 24 0-1 or 1-0 bit transitions.  Rather than
127 >     * rejecting candidates with too few or too many bits set, method
128 >     * mixGamma flips some bits (which has the effect of mapping at
129 >     * most 4 to any given gamma value).  This reduces the effective
130 >     * set of 64bit odd gamma values by about 2%, and serves as an
131       * automated screening for sequence constant selection that is
132       * left as an empirical decision in some other hashing and crypto
133       * algorithms.
# Line 134 | Line 138 | public class SplittableRandom {
138       * avalanching.
139       *
140       * The default (no-argument) constructor, in essence, invokes
141 <     * split() for a common "seeder" SplittableRandom.  Unlike other
142 <     * cases, this split must be performed in a thread-safe manner, so
143 <     * we use an AtomicLong to represent the seed rather than use an
144 <     * explicit SplittableRandom. To bootstrap the seeder, we start
145 <     * off using a seed based on current time and host. This serves as
146 <     * a slimmed-down (and insecure) variant of SecureRandom that also
147 <     * avoids stalls that may occur when using /dev/random.
141 >     * split() for a common "defaultGen" SplittableRandom.  Unlike
142 >     * other cases, this split must be performed in a thread-safe
143 >     * manner, so we use an AtomicLong to represent the seed rather
144 >     * than use an explicit SplittableRandom. To bootstrap the
145 >     * defaultGen, we start off using a seed based on current time and
146 >     * network interface address unless the java.util.secureRandomSeed
147 >     * property is set. This serves as a slimmed-down (and insecure)
148 >     * variant of SecureRandom that also avoids stalls that may occur
149 >     * when using /dev/random.
150       *
151       * It is a relatively simple matter to apply the basic design here
152       * to use 128 bit seeds. However, emulating 128bit arithmetic and
# Line 153 | Line 159 | public class SplittableRandom {
159       */
160  
161      /**
162 <     * The initial gamma value for (unsplit) SplittableRandoms. Must
163 <     * be odd with at least 12 and no more than 52 bits set. Currently
158 <     * set to the golden ratio scaled to 64bits.
162 >     * The golden ratio scaled to 64bits, used as the initial gamma
163 >     * value for (unsplit) SplittableRandoms.
164       */
165 <    private static final long INITIAL_GAMMA = 0x9e3779b97f4a7c15L;
165 >    private static final long GOLDEN_GAMMA = 0x9e3779b97f4a7c15L;
166  
167      /**
168       * The least non-zero value returned by nextDouble(). This value
169       * is scaled by a random value of 53 bits to produce a result.
170       */
171 <    private static final double DOUBLE_UNIT = 1.0 / (1L << 53);
171 >    private static final double DOUBLE_ULP = 1.0 / (1L << 53);
172  
173      /**
174       * The seed. Updated only via method nextSeed.
# Line 184 | Line 189 | public class SplittableRandom {
189      }
190  
191      /**
192 <     * Computes MurmurHash3 64bit mix function.
192 >     * Computes Stafford variant 13 of 64bit mix function.
193       */
194      private static long mix64(long z) {
195 <        z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
196 <        z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L;
197 <        return z ^ (z >>> 33);
195 >        z *= 0xbf58476d1ce4e5b9L;
196 >        z = (z ^ (z >>> 32)) * 0x94d049bb133111ebL;
197 >        return z ^ (z >>> 32);
198 >    }
199 >
200 >    private static long xmix64(long z) {
201 >        z *= 0xbf58476d1ce4e5b9L;
202 >        z = (z ^ (z >>> 27)) * 0x94d049bb133111ebL;
203 >        return z ^ (z >>> 31);
204      }
205  
206      /**
207 <     * Returns the 32 high bits of mix64(z) as int.
207 >     * Returns the 32 high bits of Stafford variant 4 mix64 function as int.
208       */
209      private static int mix32(long z) {
210 <        z = (z ^ (z >>> 33)) * 0xff51afd7ed558ccdL;
211 <        return (int)(((z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L) >>> 32);
210 >        z *= 0x62a9d9ed799705f5L;
211 >        return (int)(((z ^ (z >>> 28)) * 0xcb24d0a5c88c35b3L) >>> 32);
212      }
213  
214      /**
215       * Returns the gamma value to use for a new split instance.
216       */
217 <    private static long nextGamma(long z) {
218 <        z = (z ^ (z >>> 30)) * 0xbf58476d1ce4e5b9L; // Stafford "Mix13"
219 <        z = (z ^ (z >>> 27)) * 0x94d049bb133111ebL;
220 <        z = (z ^ (z >>> 31)) | 1L; // force to be odd
221 <        int n = Long.bitCount(z);  // ensure enough 0 and 1 bits
222 <        return (n < 12 || n > 52) ? z ^ 0xaaaaaaaaaaaaaaaaL : z;
217 >    private static long mixGamma(long z) {
218 >        z *= 0xff51afd7ed558ccdL;                   // MurmurHash3 mix constants
219 >        z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L;
220 >        z = (z ^ (z >>> 33)) | 1L;                  // force to be odd
221 >        int n = Long.bitCount(z ^ (z >>> 1));       // ensure enough transitions
222 >        return (n < 24) ? z ^ 0xaaaaaaaaaaaaaaaaL : z;
223      }
224  
225      /**
# Line 221 | Line 232 | public class SplittableRandom {
232      /**
233       * The seed generator for default constructors.
234       */
235 <    private static final AtomicLong seeder =
225 <        new AtomicLong(mix64((((long)hashedHostAddress()) << 32) ^
226 <                             System.currentTimeMillis()) ^
227 <                       mix64(System.nanoTime()));
235 >    private static final AtomicLong defaultGen = new AtomicLong(initialSeed());
236  
237 <    /**
238 <     * Returns hash of local host IP address, if available; else 0.
239 <     */
240 <    private static int hashedHostAddress() {
241 <        try {
242 <            return InetAddress.getLocalHost().hashCode();
243 <        } catch (Exception ex) {
244 <            return 0;
245 <        }
237 >    private static long initialSeed() {
238 >        String pp = java.security.AccessController.doPrivileged(
239 >                new sun.security.action.GetPropertyAction(
240 >                        "java.util.secureRandomSeed"));
241 >        if (pp != null && pp.equalsIgnoreCase("true")) {
242 >            byte[] seedBytes = java.security.SecureRandom.getSeed(8);
243 >            long s = (long)(seedBytes[0]) & 0xffL;
244 >            for (int i = 1; i < 8; ++i)
245 >                s = (s << 8) | ((long)(seedBytes[i]) & 0xffL);
246 >            return s;
247 >        }
248 >        long h = 0L;
249 >        try {
250 >            Enumeration<NetworkInterface> ifcs =
251 >                NetworkInterface.getNetworkInterfaces();
252 >            boolean retry = false; // retry once if getHardwareAddress is null
253 >            while (ifcs.hasMoreElements()) {
254 >                NetworkInterface ifc = ifcs.nextElement();
255 >                if (!ifc.isVirtual()) { // skip fake addresses
256 >                    byte[] bs = ifc.getHardwareAddress();
257 >                    if (bs != null) {
258 >                        int n = bs.length;
259 >                        int m = Math.min(n >>> 1, 4);
260 >                        for (int i = 0; i < m; ++i)
261 >                            h = (h << 16) ^ (bs[i] << 8) ^ bs[n-1-i];
262 >                        if (m < 4)
263 >                            h = (h << 8) ^ bs[n-1-m];
264 >                        h = mix64(h);
265 >                        break;
266 >                    }
267 >                    else if (!retry)
268 >                        retry = true;
269 >                    else
270 >                        break;
271 >                }
272 >            }
273 >        } catch (Exception ignore) {
274 >        }
275 >        return (h ^ mix64(System.currentTimeMillis()) ^
276 >                mix64(System.nanoTime()));
277      }
278  
279      // IllegalArgumentException messages
# Line 342 | Line 381 | public class SplittableRandom {
381       * @return a pseudorandom value
382       */
383      final double internalNextDouble(double origin, double bound) {
384 <        double r = (nextLong() >>> 11) * DOUBLE_UNIT;
384 >        double r = (nextLong() >>> 11) * DOUBLE_ULP;
385          if (origin < bound) {
386              r = r * (bound - origin) + origin;
387              if (r >= bound) // correct for rounding
# Line 361 | Line 400 | public class SplittableRandom {
400       * @param seed the initial seed
401       */
402      public SplittableRandom(long seed) {
403 <        this(seed, INITIAL_GAMMA);
403 >        this(seed, GOLDEN_GAMMA);
404      }
405  
406      /**
# Line 370 | Line 409 | public class SplittableRandom {
409       * of those of any other instances in the current program; and
410       * may, and typically does, vary across program invocations.
411       */
412 <    public SplittableRandom() { // emulate seeder.split()
413 <        this.gamma = nextGamma(this.seed = seeder.addAndGet(INITIAL_GAMMA));
412 >    public SplittableRandom() { // emulate defaultGen.split()
413 >        long s = defaultGen.getAndAdd(2*GOLDEN_GAMMA);
414 >        this.seed = mix64(s);
415 >        this.gamma = mixGamma(s + GOLDEN_GAMMA);
416      }
417  
418      /**
# Line 389 | Line 430 | public class SplittableRandom {
430       * @return the new SplittableRandom instance
431       */
432      public SplittableRandom split() {
433 <        long s = nextSeed();
393 <        return new SplittableRandom(s, nextGamma(s));
433 >        return new SplittableRandom(nextLong(), mixGamma(nextSeed()));
434      }
435  
436      /**
# Line 406 | Line 446 | public class SplittableRandom {
446       * Returns a pseudorandom {@code int} value between zero (inclusive)
447       * and the specified bound (exclusive).
448       *
449 <     * @param bound the bound on the random number to be returned.  Must be
410 <     *        positive.
449 >     * @param bound the upper bound (exclusive).  Must be positive.
450       * @return a pseudorandom {@code int} value between zero
451       *         (inclusive) and the bound (exclusive)
452 <     * @throws IllegalArgumentException if the bound is less than zero
452 >     * @throws IllegalArgumentException if {@code bound} is not positive
453       */
454      public int nextInt(int bound) {
455          if (bound <= 0)
# Line 459 | Line 498 | public class SplittableRandom {
498       * Returns a pseudorandom {@code long} value between zero (inclusive)
499       * and the specified bound (exclusive).
500       *
501 <     * @param bound the bound on the random number to be returned.  Must be
463 <     *        positive.
501 >     * @param bound the upper bound (exclusive).  Must be positive.
502       * @return a pseudorandom {@code long} value between zero
503       *         (inclusive) and the bound (exclusive)
504 <     * @throws IllegalArgumentException if {@code bound} is less than zero
504 >     * @throws IllegalArgumentException if {@code bound} is not positive
505       */
506      public long nextLong(long bound) {
507          if (bound <= 0)
# Line 504 | Line 542 | public class SplittableRandom {
542       * (inclusive) and one (exclusive).
543       *
544       * @return a pseudorandom {@code double} value between zero
545 <     * (inclusive) and one (exclusive)
545 >     *         (inclusive) and one (exclusive)
546       */
547      public double nextDouble() {
548 <        return (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT;
548 >        return (mix64(nextSeed()) >>> 11) * DOUBLE_ULP;
549      }
550  
551      /**
552       * Returns a pseudorandom {@code double} value between 0.0
553       * (inclusive) and the specified bound (exclusive).
554       *
555 <     * @param bound the bound on the random number to be returned.  Must be
518 <     *        positive.
555 >     * @param bound the upper bound (exclusive).  Must be positive.
556       * @return a pseudorandom {@code double} value between zero
557       *         (inclusive) and the bound (exclusive)
558 <     * @throws IllegalArgumentException if {@code bound} is less than zero
558 >     * @throws IllegalArgumentException if {@code bound} is not positive
559       */
560      public double nextDouble(double bound) {
561          if (!(bound > 0.0))
562              throw new IllegalArgumentException(BadBound);
563 <        double result = (mix64(nextSeed()) >>> 11) * DOUBLE_UNIT * bound;
563 >        double result = (mix64(nextSeed()) >>> 11) * DOUBLE_ULP * bound;
564          return (result < bound) ?  result : // correct for rounding
565              Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1);
566      }
# Line 533 | Line 570 | public class SplittableRandom {
570       * origin (inclusive) and bound (exclusive).
571       *
572       * @param origin the least value returned
573 <     * @param bound the upper bound
573 >     * @param bound the upper bound (exclusive)
574       * @return a pseudorandom {@code double} value between the origin
575       *         (inclusive) and the bound (exclusive)
576       * @throws IllegalArgumentException if {@code origin} is greater than
# Line 558 | Line 595 | public class SplittableRandom {
595      // maintenance purposes the small differences across forms.
596  
597      /**
598 <     * Returns a stream producing the given {@code streamSize} number of
599 <     * pseudorandom {@code int} values.
598 >     * Returns a stream producing the given {@code streamSize} number
599 >     * of pseudorandom {@code int} values from this generator and/or
600 >     * one split from it.
601       *
602       * @param streamSize the number of values to generate
603       * @return a stream of pseudorandom {@code int} values
# Line 577 | Line 615 | public class SplittableRandom {
615  
616      /**
617       * Returns an effectively unlimited stream of pseudorandom {@code int}
618 <     * values.
618 >     * values from this generator and/or one split from it.
619       *
620       * @implNote This method is implemented to be equivalent to {@code
621       * ints(Long.MAX_VALUE)}.
# Line 592 | Line 630 | public class SplittableRandom {
630      }
631  
632      /**
633 <     * Returns a stream producing the given {@code streamSize} number of
634 <     * pseudorandom {@code int} values, each conforming to the given
635 <     * origin and bound.
633 >     * Returns a stream producing the given {@code streamSize} number
634 >     * of pseudorandom {@code int} values from this generator and/or one split
635 >     * from it; each value conforms to the given origin (inclusive) and bound
636 >     * (exclusive).
637       *
638       * @param streamSize the number of values to generate
639 <     * @param randomNumberOrigin the origin of each random value
640 <     * @param randomNumberBound the bound of each random value
639 >     * @param randomNumberOrigin the origin (inclusive) of each random value
640 >     * @param randomNumberBound the bound (exclusive) of each random value
641       * @return a stream of pseudorandom {@code int} values,
642 <     *         each with the given origin and bound
642 >     *         each with the given origin (inclusive) and bound (exclusive)
643       * @throws IllegalArgumentException if {@code streamSize} is
644       *         less than zero, or {@code randomNumberOrigin}
645       *         is greater than or equal to {@code randomNumberBound}
# Line 619 | Line 658 | public class SplittableRandom {
658  
659      /**
660       * Returns an effectively unlimited stream of pseudorandom {@code
661 <     * int} values, each conforming to the given origin and bound.
661 >     * int} values from this generator and/or one split from it; each value
662 >     * conforms to the given origin (inclusive) and bound (exclusive).
663       *
664       * @implNote This method is implemented to be equivalent to {@code
665       * ints(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
666       *
667 <     * @param randomNumberOrigin the origin of each random value
668 <     * @param randomNumberBound the bound of each random value
667 >     * @param randomNumberOrigin the origin (inclusive) of each random value
668 >     * @param randomNumberBound the bound (exclusive) of each random value
669       * @return a stream of pseudorandom {@code int} values,
670 <     *         each with the given origin and bound
670 >     *         each with the given origin (inclusive) and bound (exclusive)
671       * @throws IllegalArgumentException if {@code randomNumberOrigin}
672       *         is greater than or equal to {@code randomNumberBound}
673       */
# Line 641 | Line 681 | public class SplittableRandom {
681      }
682  
683      /**
684 <     * Returns a stream producing the given {@code streamSize} number of
685 <     * pseudorandom {@code long} values.
684 >     * Returns a stream producing the given {@code streamSize} number
685 >     * of pseudorandom {@code long} values from this generator and/or
686 >     * one split from it.
687       *
688       * @param streamSize the number of values to generate
689       * @return a stream of pseudorandom {@code long} values
# Line 659 | Line 700 | public class SplittableRandom {
700      }
701  
702      /**
703 <     * Returns an effectively unlimited stream of pseudorandom {@code long}
704 <     * values.
703 >     * Returns an effectively unlimited stream of pseudorandom {@code
704 >     * long} values from this generator and/or one split from it.
705       *
706       * @implNote This method is implemented to be equivalent to {@code
707       * longs(Long.MAX_VALUE)}.
# Line 676 | Line 717 | public class SplittableRandom {
717  
718      /**
719       * Returns a stream producing the given {@code streamSize} number of
720 <     * pseudorandom {@code long} values, each conforming to the
721 <     * given origin and bound.
720 >     * pseudorandom {@code long} values from this generator and/or one split
721 >     * from it; each value conforms to the given origin (inclusive) and bound
722 >     * (exclusive).
723       *
724       * @param streamSize the number of values to generate
725 <     * @param randomNumberOrigin the origin of each random value
726 <     * @param randomNumberBound the bound of each random value
725 >     * @param randomNumberOrigin the origin (inclusive) of each random value
726 >     * @param randomNumberBound the bound (exclusive) of each random value
727       * @return a stream of pseudorandom {@code long} values,
728 <     *         each with the given origin and bound
728 >     *         each with the given origin (inclusive) and bound (exclusive)
729       * @throws IllegalArgumentException if {@code streamSize} is
730       *         less than zero, or {@code randomNumberOrigin}
731       *         is greater than or equal to {@code randomNumberBound}
# Line 702 | Line 744 | public class SplittableRandom {
744  
745      /**
746       * Returns an effectively unlimited stream of pseudorandom {@code
747 <     * long} values, each conforming to the given origin and bound.
747 >     * long} values from this generator and/or one split from it; each value
748 >     * conforms to the given origin (inclusive) and bound (exclusive).
749       *
750       * @implNote This method is implemented to be equivalent to {@code
751       * longs(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
752       *
753 <     * @param randomNumberOrigin the origin of each random value
754 <     * @param randomNumberBound the bound of each random value
753 >     * @param randomNumberOrigin the origin (inclusive) of each random value
754 >     * @param randomNumberBound the bound (exclusive) of each random value
755       * @return a stream of pseudorandom {@code long} values,
756 <     *         each with the given origin and bound
756 >     *         each with the given origin (inclusive) and bound (exclusive)
757       * @throws IllegalArgumentException if {@code randomNumberOrigin}
758       *         is greater than or equal to {@code randomNumberBound}
759       */
# Line 725 | Line 768 | public class SplittableRandom {
768  
769      /**
770       * Returns a stream producing the given {@code streamSize} number of
771 <     * pseudorandom {@code double} values, each between zero
772 <     * (inclusive) and one (exclusive).
771 >     * pseudorandom {@code double} values from this generator and/or one split
772 >     * from it; each value is between zero (inclusive) and one (exclusive).
773       *
774       * @param streamSize the number of values to generate
775       * @return a stream of {@code double} values
# Line 744 | Line 787 | public class SplittableRandom {
787  
788      /**
789       * Returns an effectively unlimited stream of pseudorandom {@code
790 <     * double} values, each between zero (inclusive) and one
791 <     * (exclusive).
790 >     * double} values from this generator and/or one split from it; each value
791 >     * is between zero (inclusive) and one (exclusive).
792       *
793       * @implNote This method is implemented to be equivalent to {@code
794       * doubles(Long.MAX_VALUE)}.
# Line 761 | Line 804 | public class SplittableRandom {
804  
805      /**
806       * Returns a stream producing the given {@code streamSize} number of
807 <     * pseudorandom {@code double} values, each conforming to the
808 <     * given origin and bound.
807 >     * pseudorandom {@code double} values from this generator and/or one split
808 >     * from it; each value conforms to the given origin (inclusive) and bound
809 >     * (exclusive).
810       *
811       * @param streamSize the number of values to generate
812 <     * @param randomNumberOrigin the origin of each random value
813 <     * @param randomNumberBound the bound of each random value
812 >     * @param randomNumberOrigin the origin (inclusive) of each random value
813 >     * @param randomNumberBound the bound (exclusive) of each random value
814       * @return a stream of pseudorandom {@code double} values,
815 <     * each with the given origin and bound
815 >     *         each with the given origin (inclusive) and bound (exclusive)
816       * @throws IllegalArgumentException if {@code streamSize} is
817 <     * less than zero
817 >     *         less than zero
818       * @throws IllegalArgumentException if {@code randomNumberOrigin}
819       *         is greater than or equal to {@code randomNumberBound}
820       */
# Line 788 | Line 832 | public class SplittableRandom {
832  
833      /**
834       * Returns an effectively unlimited stream of pseudorandom {@code
835 <     * double} values, each conforming to the given origin and bound.
835 >     * double} values from this generator and/or one split from it; each value
836 >     * conforms to the given origin (inclusive) and bound (exclusive).
837       *
838       * @implNote This method is implemented to be equivalent to {@code
839       * doubles(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}.
840       *
841 <     * @param randomNumberOrigin the origin of each random value
842 <     * @param randomNumberBound the bound of each random value
841 >     * @param randomNumberOrigin the origin (inclusive) of each random value
842 >     * @param randomNumberBound the bound (exclusive) of each random value
843       * @return a stream of pseudorandom {@code double} values,
844 <     * each with the given origin and bound
844 >     *         each with the given origin (inclusive) and bound (exclusive)
845       * @throws IllegalArgumentException if {@code randomNumberOrigin}
846       *         is greater than or equal to {@code randomNumberBound}
847       */

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