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1.1 |
/* |
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* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.util; |
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1.18 |
import java.security.SecureRandom; |
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1.21 |
import java.net.NetworkInterface; |
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import java.util.Enumeration; |
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1.1 |
import java.util.concurrent.atomic.AtomicLong; |
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import java.util.function.IntConsumer; |
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import java.util.function.LongConsumer; |
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import java.util.function.DoubleConsumer; |
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import java.util.stream.StreamSupport; |
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import java.util.stream.IntStream; |
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import java.util.stream.LongStream; |
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import java.util.stream.DoubleStream; |
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/** |
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* A generator of uniform pseudorandom values applicable for use in |
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* (among other contexts) isolated parallel computations that may |
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dl |
1.18 |
* generate subtasks. Class {@code SplittableRandom} supports methods for |
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jsr166 |
1.3 |
* producing pseudorandom numbers of type {@code int}, {@code long}, |
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1.1 |
* and {@code double} with similar usages as for class |
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jsr166 |
1.9 |
* {@link java.util.Random} but differs in the following ways: |
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* |
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* <ul> |
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dl |
1.1 |
* |
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* <li>Series of generated values pass the DieHarder suite testing |
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* independence and uniformity properties of random number generators. |
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* (Most recently validated with <a |
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* href="http://www.phy.duke.edu/~rgb/General/dieharder.php"> version |
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* 3.31.1</a>.) These tests validate only the methods for certain |
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* types and ranges, but similar properties are expected to hold, at |
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dl |
1.11 |
* least approximately, for others as well. The <em>period</em> |
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* (length of any series of generated values before it repeats) is at |
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* least 2<sup>64</sup>. </li> |
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dl |
1.1 |
* |
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* <li> Method {@link #split} constructs and returns a new |
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* SplittableRandom instance that shares no mutable state with the |
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dl |
1.7 |
* current instance. However, with very high probability, the |
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* values collectively generated by the two objects have the same |
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dl |
1.1 |
* statistical properties as if the same quantity of values were |
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* generated by a single thread using a single {@code |
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* SplittableRandom} object. </li> |
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* |
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* <li>Instances of SplittableRandom are <em>not</em> thread-safe. |
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* They are designed to be split, not shared, across threads. For |
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* example, a {@link java.util.concurrent.ForkJoinTask |
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* fork/join-style} computation using random numbers might include a |
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* construction of the form {@code new |
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* Subtask(aSplittableRandom.split()).fork()}. |
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* |
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* <li>This class provides additional methods for generating random |
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* streams, that employ the above techniques when used in {@code |
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* stream.parallel()} mode.</li> |
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* |
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* </ul> |
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* |
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dl |
1.18 |
* <p>Instances of {@code SplittableRandom} are not cryptographically |
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* secure. Consider instead using {@link java.security.SecureRandom} |
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* in security-sensitive applications. Additionally, |
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* default-constructed instances do not use a cryptographically random |
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* seed unless the {@linkplain System#getProperty system property} |
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* {@code java.util.secureRandomSeed} is set to {@code true}. |
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* |
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1.1 |
* @author Guy Steele |
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1.2 |
* @author Doug Lea |
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1.1 |
* @since 1.8 |
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*/ |
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public class SplittableRandom { |
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/* |
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* Implementation Overview. |
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* |
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* This algorithm was inspired by the "DotMix" algorithm by |
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* Leiserson, Schardl, and Sukha "Deterministic Parallel |
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* Random-Number Generation for Dynamic-Multithreading Platforms", |
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dl |
1.15 |
* PPoPP 2012, as well as those in "Parallel random numbers: as |
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* easy as 1, 2, 3" by Salmon, Morae, Dror, and Shaw, SC 2011. It |
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* differs mainly in simplifying and cheapening operations. |
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* |
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* The primary update step (method nextSeed()) is to add a |
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* constant ("gamma") to the current (64 bit) seed, forming a |
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* simple sequence. The seed and the gamma values for any two |
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* SplittableRandom instances are highly likely to be different. |
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* |
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* Methods nextLong, nextInt, and derivatives do not return the |
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* sequence (seed) values, but instead a hash-like bit-mix of |
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* their bits, producing more independently distributed sequences. |
112 |
dl |
1.21 |
* For nextLong, the mix64 function is based on David Stafford's |
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* (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html) |
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* "Mix13" variant of the "64-bit finalizer" function in Austin |
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* Appleby's MurmurHash3 algorithm See |
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* http://code.google.com/p/smhasher/wiki/MurmurHash3 . The mix32 |
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* function is based on Stafford's Mix04 mix function, but returns |
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* the upper 32 bits cast as int. |
119 |
dl |
1.15 |
* |
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* The split operation uses the current generator to form the seed |
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* and gamma for another SplittableRandom. To conservatively |
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* avoid potential correlations between seed and value generation, |
123 |
dl |
1.21 |
* gamma selection (method mixGamma) uses different |
124 |
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* (Murmurhash3's) mix constants. To avoid potential weaknesses |
125 |
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* in bit-mixing transformations, we restrict gammas to odd values |
126 |
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* with at least 24 0-1 or 1-0 bit transitions. Rather than |
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* rejecting candidates with too few or too many bits set, method |
128 |
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* mixGamma flips some bits (which has the effect of mapping at |
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* most 4 to any given gamma value). This reduces the effective |
130 |
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* set of 64bit odd gamma values by about 2%, and serves as an |
131 |
dl |
1.15 |
* automated screening for sequence constant selection that is |
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* left as an empirical decision in some other hashing and crypto |
133 |
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* algorithms. |
134 |
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* |
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* The resulting generator thus transforms a sequence in which |
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* (typically) many bits change on each step, with an inexpensive |
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* mixer with good (but less than cryptographically secure) |
138 |
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* avalanching. |
139 |
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* |
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* The default (no-argument) constructor, in essence, invokes |
141 |
dl |
1.21 |
* split() for a common "defaultGen" SplittableRandom. Unlike |
142 |
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* other cases, this split must be performed in a thread-safe |
143 |
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* manner, so we use an AtomicLong to represent the seed rather |
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* than use an explicit SplittableRandom. To bootstrap the |
145 |
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* defaultGen, we start off using a seed based on current time and |
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* network interface address unless the java.util.secureRandomSeed |
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* property is set. This serves as a slimmed-down (and insecure) |
148 |
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* variant of SecureRandom that also avoids stalls that may occur |
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* when using /dev/random. |
150 |
dl |
1.15 |
* |
151 |
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* It is a relatively simple matter to apply the basic design here |
152 |
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* to use 128 bit seeds. However, emulating 128bit arithmetic and |
153 |
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* carrying around twice the state add more overhead than appears |
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* warranted for current usages. |
155 |
dl |
1.13 |
* |
156 |
dl |
1.15 |
* File organization: First the non-public methods that constitute |
157 |
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* the main algorithm, then the main public methods, followed by |
158 |
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* some custom spliterator classes needed for stream methods. |
159 |
dl |
1.1 |
*/ |
160 |
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161 |
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/** |
162 |
dl |
1.21 |
* The golden ratio scaled to 64bits, used as the initial gamma |
163 |
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* value for (unsplit) SplittableRandoms. |
164 |
dl |
1.1 |
*/ |
165 |
dl |
1.21 |
private static final long GOLDEN_GAMMA = 0x9e3779b97f4a7c15L; |
166 |
dl |
1.11 |
|
167 |
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/** |
168 |
dl |
1.5 |
* The least non-zero value returned by nextDouble(). This value |
169 |
dl |
1.7 |
* is scaled by a random value of 53 bits to produce a result. |
170 |
dl |
1.5 |
*/ |
171 |
dl |
1.21 |
private static final double DOUBLE_ULP = 1.0 / (1L << 53); |
172 |
dl |
1.5 |
|
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/** |
174 |
dl |
1.15 |
* The seed. Updated only via method nextSeed. |
175 |
dl |
1.1 |
*/ |
176 |
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private long seed; |
177 |
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178 |
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/** |
179 |
dl |
1.15 |
* The step value. |
180 |
dl |
1.1 |
*/ |
181 |
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private final long gamma; |
182 |
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183 |
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/** |
184 |
dl |
1.15 |
* Internal constructor used by all others except default constructor. |
185 |
dl |
1.1 |
*/ |
186 |
dl |
1.15 |
private SplittableRandom(long seed, long gamma) { |
187 |
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this.seed = seed; |
188 |
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this.gamma = gamma; |
189 |
dl |
1.1 |
} |
190 |
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191 |
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/** |
192 |
dl |
1.21 |
* Computes Stafford variant 13 of 64bit mix function. |
193 |
dl |
1.1 |
*/ |
194 |
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private static long mix64(long z) { |
195 |
dl |
1.21 |
z *= 0xbf58476d1ce4e5b9L; |
196 |
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z = (z ^ (z >>> 32)) * 0x94d049bb133111ebL; |
197 |
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return z ^ (z >>> 32); |
198 |
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} |
199 |
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200 |
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private static long xmix64(long z) { |
201 |
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z *= 0xbf58476d1ce4e5b9L; |
202 |
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z = (z ^ (z >>> 27)) * 0x94d049bb133111ebL; |
203 |
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return z ^ (z >>> 31); |
204 |
dl |
1.1 |
} |
205 |
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206 |
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/** |
207 |
dl |
1.21 |
* Returns the 32 high bits of Stafford variant 4 mix64 function as int. |
208 |
dl |
1.1 |
*/ |
209 |
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private static int mix32(long z) { |
210 |
dl |
1.21 |
z *= 0x62a9d9ed799705f5L; |
211 |
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return (int)(((z ^ (z >>> 28)) * 0xcb24d0a5c88c35b3L) >>> 32); |
212 |
dl |
1.1 |
} |
213 |
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|
214 |
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/** |
215 |
dl |
1.15 |
* Returns the gamma value to use for a new split instance. |
216 |
dl |
1.13 |
*/ |
217 |
dl |
1.21 |
private static long mixGamma(long z) { |
218 |
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z *= 0xff51afd7ed558ccdL; // MurmurHash3 mix constants |
219 |
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z = (z ^ (z >>> 33)) * 0xc4ceb9fe1a85ec53L; |
220 |
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z = (z ^ (z >>> 33)) | 1L; // force to be odd |
221 |
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int n = Long.bitCount(z ^ (z >>> 1)); // ensure enough transitions |
222 |
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return (n < 24) ? z ^ 0xaaaaaaaaaaaaaaaaL : z; |
223 |
dl |
1.13 |
} |
224 |
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|
225 |
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/** |
226 |
dl |
1.15 |
* Adds gamma to seed. |
227 |
dl |
1.7 |
*/ |
228 |
dl |
1.15 |
private long nextSeed() { |
229 |
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return seed += gamma; |
230 |
dl |
1.7 |
} |
231 |
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|
232 |
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/** |
233 |
dl |
1.15 |
* The seed generator for default constructors. |
234 |
dl |
1.7 |
*/ |
235 |
dl |
1.21 |
private static final AtomicLong defaultGen = new AtomicLong(initialSeed()); |
236 |
dl |
1.7 |
|
237 |
dl |
1.18 |
private static long initialSeed() { |
238 |
dl |
1.21 |
String pp = java.security.AccessController.doPrivileged( |
239 |
|
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new sun.security.action.GetPropertyAction( |
240 |
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"java.util.secureRandomSeed")); |
241 |
|
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if (pp != null && pp.equalsIgnoreCase("true")) { |
242 |
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byte[] seedBytes = java.security.SecureRandom.getSeed(8); |
243 |
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long s = (long)(seedBytes[0]) & 0xffL; |
244 |
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for (int i = 1; i < 8; ++i) |
245 |
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s = (s << 8) | ((long)(seedBytes[i]) & 0xffL); |
246 |
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return s; |
247 |
dl |
1.18 |
} |
248 |
dl |
1.21 |
long h = 0L; |
249 |
jsr166 |
1.17 |
try { |
250 |
dl |
1.21 |
Enumeration<NetworkInterface> ifcs = |
251 |
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NetworkInterface.getNetworkInterfaces(); |
252 |
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boolean retry = false; // retry once if getHardwareAddress is null |
253 |
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while (ifcs.hasMoreElements()) { |
254 |
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NetworkInterface ifc = ifcs.nextElement(); |
255 |
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if (!ifc.isVirtual()) { // skip fake addresses |
256 |
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byte[] bs = ifc.getHardwareAddress(); |
257 |
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if (bs != null) { |
258 |
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int n = bs.length; |
259 |
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int m = Math.min(n >>> 1, 4); |
260 |
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for (int i = 0; i < m; ++i) |
261 |
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h = (h << 16) ^ (bs[i] << 8) ^ bs[n-1-i]; |
262 |
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if (m < 4) |
263 |
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h = (h << 8) ^ bs[n-1-m]; |
264 |
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h = mix64(h); |
265 |
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break; |
266 |
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} |
267 |
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else if (!retry) |
268 |
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retry = true; |
269 |
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else |
270 |
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break; |
271 |
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} |
272 |
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} |
273 |
dl |
1.18 |
} catch (Exception ignore) { |
274 |
jsr166 |
1.17 |
} |
275 |
dl |
1.21 |
return (h ^ mix64(System.currentTimeMillis()) ^ |
276 |
dl |
1.18 |
mix64(System.nanoTime())); |
277 |
dl |
1.1 |
} |
278 |
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|
279 |
dl |
1.15 |
// IllegalArgumentException messages |
280 |
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static final String BadBound = "bound must be positive"; |
281 |
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static final String BadRange = "bound must be greater than origin"; |
282 |
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static final String BadSize = "size must be non-negative"; |
283 |
dl |
1.12 |
|
284 |
dl |
1.1 |
/* |
285 |
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* Internal versions of nextX methods used by streams, as well as |
286 |
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* the public nextX(origin, bound) methods. These exist mainly to |
287 |
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* avoid the need for multiple versions of stream spliterators |
288 |
|
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* across the different exported forms of streams. |
289 |
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*/ |
290 |
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|
291 |
|
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/** |
292 |
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* The form of nextLong used by LongStream Spliterators. If |
293 |
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* origin is greater than bound, acts as unbounded form of |
294 |
|
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* nextLong, else as bounded form. |
295 |
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* |
296 |
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* @param origin the least value, unless greater than bound |
297 |
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* @param bound the upper bound (exclusive), must not equal origin |
298 |
|
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* @return a pseudorandom value |
299 |
|
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*/ |
300 |
|
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final long internalNextLong(long origin, long bound) { |
301 |
|
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/* |
302 |
|
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* Four Cases: |
303 |
|
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* |
304 |
|
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* 1. If the arguments indicate unbounded form, act as |
305 |
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* nextLong(). |
306 |
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* |
307 |
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* 2. If the range is an exact power of two, apply the |
308 |
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* associated bit mask. |
309 |
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* |
310 |
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* 3. If the range is positive, loop to avoid potential bias |
311 |
|
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* when the implicit nextLong() bound (2<sup>64</sup>) is not |
312 |
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* evenly divisible by the range. The loop rejects candidates |
313 |
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* computed from otherwise over-represented values. The |
314 |
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* expected number of iterations under an ideal generator |
315 |
dl |
1.4 |
* varies from 1 to 2, depending on the bound. The loop itself |
316 |
|
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* takes an unlovable form. Because the first candidate is |
317 |
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* already available, we need a break-in-the-middle |
318 |
|
|
* construction, which is concisely but cryptically performed |
319 |
|
|
* within the while-condition of a body-less for loop. |
320 |
dl |
1.1 |
* |
321 |
|
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* 4. Otherwise, the range cannot be represented as a positive |
322 |
dl |
1.4 |
* long. The loop repeatedly generates unbounded longs until |
323 |
|
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* obtaining a candidate meeting constraints (with an expected |
324 |
|
|
* number of iterations of less than two). |
325 |
dl |
1.1 |
*/ |
326 |
|
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|
327 |
|
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long r = mix64(nextSeed()); |
328 |
|
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if (origin < bound) { |
329 |
|
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long n = bound - origin, m = n - 1; |
330 |
dl |
1.7 |
if ((n & m) == 0L) // power of two |
331 |
dl |
1.1 |
r = (r & m) + origin; |
332 |
dl |
1.7 |
else if (n > 0L) { // reject over-represented candidates |
333 |
dl |
1.1 |
for (long u = r >>> 1; // ensure nonnegative |
334 |
dl |
1.7 |
u + m - (r = u % n) < 0L; // rejection check |
335 |
dl |
1.1 |
u = mix64(nextSeed()) >>> 1) // retry |
336 |
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; |
337 |
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r += origin; |
338 |
|
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} |
339 |
dl |
1.7 |
else { // range not representable as long |
340 |
dl |
1.1 |
while (r < origin || r >= bound) |
341 |
|
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r = mix64(nextSeed()); |
342 |
|
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} |
343 |
|
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} |
344 |
|
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return r; |
345 |
|
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} |
346 |
|
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|
347 |
|
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/** |
348 |
|
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* The form of nextInt used by IntStream Spliterators. |
349 |
|
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* Exactly the same as long version, except for types. |
350 |
|
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* |
351 |
|
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* @param origin the least value, unless greater than bound |
352 |
|
|
* @param bound the upper bound (exclusive), must not equal origin |
353 |
|
|
* @return a pseudorandom value |
354 |
|
|
*/ |
355 |
|
|
final int internalNextInt(int origin, int bound) { |
356 |
|
|
int r = mix32(nextSeed()); |
357 |
|
|
if (origin < bound) { |
358 |
|
|
int n = bound - origin, m = n - 1; |
359 |
dl |
1.13 |
if ((n & m) == 0) |
360 |
dl |
1.1 |
r = (r & m) + origin; |
361 |
|
|
else if (n > 0) { |
362 |
|
|
for (int u = r >>> 1; |
363 |
dl |
1.7 |
u + m - (r = u % n) < 0; |
364 |
dl |
1.1 |
u = mix32(nextSeed()) >>> 1) |
365 |
|
|
; |
366 |
|
|
r += origin; |
367 |
|
|
} |
368 |
|
|
else { |
369 |
|
|
while (r < origin || r >= bound) |
370 |
|
|
r = mix32(nextSeed()); |
371 |
|
|
} |
372 |
|
|
} |
373 |
|
|
return r; |
374 |
|
|
} |
375 |
|
|
|
376 |
|
|
/** |
377 |
|
|
* The form of nextDouble used by DoubleStream Spliterators. |
378 |
|
|
* |
379 |
|
|
* @param origin the least value, unless greater than bound |
380 |
|
|
* @param bound the upper bound (exclusive), must not equal origin |
381 |
|
|
* @return a pseudorandom value |
382 |
|
|
*/ |
383 |
|
|
final double internalNextDouble(double origin, double bound) { |
384 |
dl |
1.21 |
double r = (nextLong() >>> 11) * DOUBLE_ULP; |
385 |
dl |
1.1 |
if (origin < bound) { |
386 |
|
|
r = r * (bound - origin) + origin; |
387 |
dl |
1.7 |
if (r >= bound) // correct for rounding |
388 |
dl |
1.1 |
r = Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1); |
389 |
|
|
} |
390 |
|
|
return r; |
391 |
|
|
} |
392 |
|
|
|
393 |
|
|
/* ---------------- public methods ---------------- */ |
394 |
|
|
|
395 |
|
|
/** |
396 |
dl |
1.7 |
* Creates a new SplittableRandom instance using the specified |
397 |
|
|
* initial seed. SplittableRandom instances created with the same |
398 |
dl |
1.11 |
* seed in the same program generate identical sequences of values. |
399 |
dl |
1.1 |
* |
400 |
|
|
* @param seed the initial seed |
401 |
|
|
*/ |
402 |
|
|
public SplittableRandom(long seed) { |
403 |
dl |
1.21 |
this(seed, GOLDEN_GAMMA); |
404 |
dl |
1.1 |
} |
405 |
|
|
|
406 |
|
|
/** |
407 |
|
|
* Creates a new SplittableRandom instance that is likely to |
408 |
|
|
* generate sequences of values that are statistically independent |
409 |
|
|
* of those of any other instances in the current program; and |
410 |
|
|
* may, and typically does, vary across program invocations. |
411 |
|
|
*/ |
412 |
dl |
1.21 |
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 |
dl |
1.1 |
} |
417 |
|
|
|
418 |
|
|
/** |
419 |
|
|
* Constructs and returns a new SplittableRandom instance that |
420 |
|
|
* shares no mutable state with this instance. However, with very |
421 |
|
|
* high probability, the set of values collectively generated by |
422 |
|
|
* the two objects has the same statistical properties as if the |
423 |
|
|
* same quantity of values were generated by a single thread using |
424 |
|
|
* a single SplittableRandom object. Either or both of the two |
425 |
|
|
* objects may be further split using the {@code split()} method, |
426 |
|
|
* and the same expected statistical properties apply to the |
427 |
|
|
* entire set of generators constructed by such recursive |
428 |
|
|
* splitting. |
429 |
|
|
* |
430 |
|
|
* @return the new SplittableRandom instance |
431 |
|
|
*/ |
432 |
|
|
public SplittableRandom split() { |
433 |
dl |
1.21 |
return new SplittableRandom(nextLong(), mixGamma(nextSeed())); |
434 |
dl |
1.1 |
} |
435 |
|
|
|
436 |
|
|
/** |
437 |
|
|
* Returns a pseudorandom {@code int} value. |
438 |
|
|
* |
439 |
dl |
1.7 |
* @return a pseudorandom {@code int} value |
440 |
dl |
1.1 |
*/ |
441 |
|
|
public int nextInt() { |
442 |
|
|
return mix32(nextSeed()); |
443 |
|
|
} |
444 |
|
|
|
445 |
|
|
/** |
446 |
dl |
1.7 |
* Returns a pseudorandom {@code int} value between zero (inclusive) |
447 |
dl |
1.1 |
* and the specified bound (exclusive). |
448 |
|
|
* |
449 |
dl |
1.18 |
* @param bound the upper bound (exclusive). Must be positive. |
450 |
dl |
1.7 |
* @return a pseudorandom {@code int} value between zero |
451 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
452 |
dl |
1.16 |
* @throws IllegalArgumentException if {@code bound} is not positive |
453 |
dl |
1.1 |
*/ |
454 |
|
|
public int nextInt(int bound) { |
455 |
|
|
if (bound <= 0) |
456 |
dl |
1.15 |
throw new IllegalArgumentException(BadBound); |
457 |
dl |
1.1 |
// Specialize internalNextInt for origin 0 |
458 |
|
|
int r = mix32(nextSeed()); |
459 |
|
|
int m = bound - 1; |
460 |
dl |
1.13 |
if ((bound & m) == 0) // power of two |
461 |
dl |
1.1 |
r &= m; |
462 |
|
|
else { // reject over-represented candidates |
463 |
|
|
for (int u = r >>> 1; |
464 |
dl |
1.7 |
u + m - (r = u % bound) < 0; |
465 |
dl |
1.1 |
u = mix32(nextSeed()) >>> 1) |
466 |
|
|
; |
467 |
|
|
} |
468 |
|
|
return r; |
469 |
|
|
} |
470 |
|
|
|
471 |
|
|
/** |
472 |
|
|
* Returns a pseudorandom {@code int} value between the specified |
473 |
|
|
* origin (inclusive) and the specified bound (exclusive). |
474 |
|
|
* |
475 |
|
|
* @param origin the least value returned |
476 |
|
|
* @param bound the upper bound (exclusive) |
477 |
|
|
* @return a pseudorandom {@code int} value between the origin |
478 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
479 |
dl |
1.7 |
* @throws IllegalArgumentException if {@code origin} is greater than |
480 |
dl |
1.1 |
* or equal to {@code bound} |
481 |
|
|
*/ |
482 |
|
|
public int nextInt(int origin, int bound) { |
483 |
|
|
if (origin >= bound) |
484 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
485 |
dl |
1.1 |
return internalNextInt(origin, bound); |
486 |
|
|
} |
487 |
|
|
|
488 |
|
|
/** |
489 |
|
|
* Returns a pseudorandom {@code long} value. |
490 |
|
|
* |
491 |
dl |
1.7 |
* @return a pseudorandom {@code long} value |
492 |
dl |
1.1 |
*/ |
493 |
|
|
public long nextLong() { |
494 |
|
|
return mix64(nextSeed()); |
495 |
|
|
} |
496 |
|
|
|
497 |
|
|
/** |
498 |
dl |
1.7 |
* Returns a pseudorandom {@code long} value between zero (inclusive) |
499 |
dl |
1.1 |
* and the specified bound (exclusive). |
500 |
|
|
* |
501 |
dl |
1.18 |
* @param bound the upper bound (exclusive). Must be positive. |
502 |
dl |
1.7 |
* @return a pseudorandom {@code long} value between zero |
503 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
504 |
dl |
1.16 |
* @throws IllegalArgumentException if {@code bound} is not positive |
505 |
dl |
1.1 |
*/ |
506 |
|
|
public long nextLong(long bound) { |
507 |
|
|
if (bound <= 0) |
508 |
dl |
1.15 |
throw new IllegalArgumentException(BadBound); |
509 |
dl |
1.1 |
// Specialize internalNextLong for origin 0 |
510 |
|
|
long r = mix64(nextSeed()); |
511 |
|
|
long m = bound - 1; |
512 |
|
|
if ((bound & m) == 0L) // power of two |
513 |
|
|
r &= m; |
514 |
|
|
else { // reject over-represented candidates |
515 |
|
|
for (long u = r >>> 1; |
516 |
|
|
u + m - (r = u % bound) < 0L; |
517 |
|
|
u = mix64(nextSeed()) >>> 1) |
518 |
|
|
; |
519 |
|
|
} |
520 |
|
|
return r; |
521 |
|
|
} |
522 |
|
|
|
523 |
|
|
/** |
524 |
|
|
* Returns a pseudorandom {@code long} value between the specified |
525 |
|
|
* origin (inclusive) and the specified bound (exclusive). |
526 |
|
|
* |
527 |
|
|
* @param origin the least value returned |
528 |
|
|
* @param bound the upper bound (exclusive) |
529 |
|
|
* @return a pseudorandom {@code long} value between the origin |
530 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
531 |
dl |
1.7 |
* @throws IllegalArgumentException if {@code origin} is greater than |
532 |
dl |
1.1 |
* or equal to {@code bound} |
533 |
|
|
*/ |
534 |
|
|
public long nextLong(long origin, long bound) { |
535 |
|
|
if (origin >= bound) |
536 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
537 |
dl |
1.1 |
return internalNextLong(origin, bound); |
538 |
|
|
} |
539 |
|
|
|
540 |
|
|
/** |
541 |
dl |
1.7 |
* Returns a pseudorandom {@code double} value between zero |
542 |
|
|
* (inclusive) and one (exclusive). |
543 |
dl |
1.1 |
* |
544 |
dl |
1.7 |
* @return a pseudorandom {@code double} value between zero |
545 |
dl |
1.18 |
* (inclusive) and one (exclusive) |
546 |
dl |
1.1 |
*/ |
547 |
|
|
public double nextDouble() { |
548 |
dl |
1.21 |
return (mix64(nextSeed()) >>> 11) * DOUBLE_ULP; |
549 |
dl |
1.1 |
} |
550 |
|
|
|
551 |
|
|
/** |
552 |
|
|
* Returns a pseudorandom {@code double} value between 0.0 |
553 |
|
|
* (inclusive) and the specified bound (exclusive). |
554 |
|
|
* |
555 |
dl |
1.18 |
* @param bound the upper bound (exclusive). Must be positive. |
556 |
dl |
1.7 |
* @return a pseudorandom {@code double} value between zero |
557 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
558 |
dl |
1.16 |
* @throws IllegalArgumentException if {@code bound} is not positive |
559 |
dl |
1.1 |
*/ |
560 |
|
|
public double nextDouble(double bound) { |
561 |
dl |
1.7 |
if (!(bound > 0.0)) |
562 |
dl |
1.15 |
throw new IllegalArgumentException(BadBound); |
563 |
dl |
1.21 |
double result = (mix64(nextSeed()) >>> 11) * DOUBLE_ULP * bound; |
564 |
dl |
1.1 |
return (result < bound) ? result : // correct for rounding |
565 |
|
|
Double.longBitsToDouble(Double.doubleToLongBits(bound) - 1); |
566 |
|
|
} |
567 |
|
|
|
568 |
|
|
/** |
569 |
dl |
1.7 |
* Returns a pseudorandom {@code double} value between the specified |
570 |
dl |
1.1 |
* origin (inclusive) and bound (exclusive). |
571 |
|
|
* |
572 |
|
|
* @param origin the least value returned |
573 |
dl |
1.18 |
* @param bound the upper bound (exclusive) |
574 |
dl |
1.1 |
* @return a pseudorandom {@code double} value between the origin |
575 |
jsr166 |
1.10 |
* (inclusive) and the bound (exclusive) |
576 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code origin} is greater than |
577 |
|
|
* or equal to {@code bound} |
578 |
|
|
*/ |
579 |
|
|
public double nextDouble(double origin, double bound) { |
580 |
dl |
1.7 |
if (!(origin < bound)) |
581 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
582 |
dl |
1.1 |
return internalNextDouble(origin, bound); |
583 |
|
|
} |
584 |
|
|
|
585 |
dl |
1.11 |
/** |
586 |
|
|
* Returns a pseudorandom {@code boolean} value. |
587 |
|
|
* |
588 |
|
|
* @return a pseudorandom {@code boolean} value |
589 |
|
|
*/ |
590 |
|
|
public boolean nextBoolean() { |
591 |
|
|
return mix32(nextSeed()) < 0; |
592 |
|
|
} |
593 |
|
|
|
594 |
dl |
1.1 |
// stream methods, coded in a way intended to better isolate for |
595 |
|
|
// maintenance purposes the small differences across forms. |
596 |
|
|
|
597 |
|
|
/** |
598 |
dl |
1.16 |
* 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 |
dl |
1.1 |
* |
602 |
|
|
* @param streamSize the number of values to generate |
603 |
|
|
* @return a stream of pseudorandom {@code int} values |
604 |
|
|
* @throws IllegalArgumentException if {@code streamSize} is |
605 |
dl |
1.7 |
* less than zero |
606 |
dl |
1.1 |
*/ |
607 |
|
|
public IntStream ints(long streamSize) { |
608 |
|
|
if (streamSize < 0L) |
609 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
610 |
dl |
1.1 |
return StreamSupport.intStream |
611 |
|
|
(new RandomIntsSpliterator |
612 |
|
|
(this, 0L, streamSize, Integer.MAX_VALUE, 0), |
613 |
|
|
false); |
614 |
|
|
} |
615 |
|
|
|
616 |
|
|
/** |
617 |
|
|
* Returns an effectively unlimited stream of pseudorandom {@code int} |
618 |
dl |
1.16 |
* values from this generator and/or one split from it. |
619 |
dl |
1.1 |
* |
620 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
621 |
|
|
* ints(Long.MAX_VALUE)}. |
622 |
|
|
* |
623 |
|
|
* @return a stream of pseudorandom {@code int} values |
624 |
|
|
*/ |
625 |
|
|
public IntStream ints() { |
626 |
|
|
return StreamSupport.intStream |
627 |
|
|
(new RandomIntsSpliterator |
628 |
|
|
(this, 0L, Long.MAX_VALUE, Integer.MAX_VALUE, 0), |
629 |
|
|
false); |
630 |
|
|
} |
631 |
|
|
|
632 |
|
|
/** |
633 |
dl |
1.16 |
* Returns a stream producing the given {@code streamSize} number |
634 |
dl |
1.18 |
* 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 |
dl |
1.1 |
* |
638 |
|
|
* @param streamSize the number of values to generate |
639 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
640 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
641 |
dl |
1.1 |
* @return a stream of pseudorandom {@code int} values, |
642 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
643 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code streamSize} is |
644 |
dl |
1.7 |
* less than zero, or {@code randomNumberOrigin} |
645 |
dl |
1.1 |
* is greater than or equal to {@code randomNumberBound} |
646 |
|
|
*/ |
647 |
|
|
public IntStream ints(long streamSize, int randomNumberOrigin, |
648 |
|
|
int randomNumberBound) { |
649 |
|
|
if (streamSize < 0L) |
650 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
651 |
dl |
1.1 |
if (randomNumberOrigin >= randomNumberBound) |
652 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
653 |
dl |
1.1 |
return StreamSupport.intStream |
654 |
|
|
(new RandomIntsSpliterator |
655 |
|
|
(this, 0L, streamSize, randomNumberOrigin, randomNumberBound), |
656 |
|
|
false); |
657 |
|
|
} |
658 |
|
|
|
659 |
|
|
/** |
660 |
|
|
* Returns an effectively unlimited stream of pseudorandom {@code |
661 |
dl |
1.18 |
* int} values from this generator and/or one split from it; each value |
662 |
|
|
* conforms to the given origin (inclusive) and bound (exclusive). |
663 |
dl |
1.1 |
* |
664 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
665 |
|
|
* ints(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}. |
666 |
|
|
* |
667 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
668 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
669 |
dl |
1.1 |
* @return a stream of pseudorandom {@code int} values, |
670 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
671 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code randomNumberOrigin} |
672 |
|
|
* is greater than or equal to {@code randomNumberBound} |
673 |
|
|
*/ |
674 |
|
|
public IntStream ints(int randomNumberOrigin, int randomNumberBound) { |
675 |
|
|
if (randomNumberOrigin >= randomNumberBound) |
676 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
677 |
dl |
1.1 |
return StreamSupport.intStream |
678 |
|
|
(new RandomIntsSpliterator |
679 |
|
|
(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound), |
680 |
|
|
false); |
681 |
|
|
} |
682 |
|
|
|
683 |
|
|
/** |
684 |
dl |
1.16 |
* 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 |
dl |
1.1 |
* |
688 |
|
|
* @param streamSize the number of values to generate |
689 |
dl |
1.7 |
* @return a stream of pseudorandom {@code long} values |
690 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code streamSize} is |
691 |
dl |
1.7 |
* less than zero |
692 |
dl |
1.1 |
*/ |
693 |
|
|
public LongStream longs(long streamSize) { |
694 |
|
|
if (streamSize < 0L) |
695 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
696 |
dl |
1.1 |
return StreamSupport.longStream |
697 |
|
|
(new RandomLongsSpliterator |
698 |
|
|
(this, 0L, streamSize, Long.MAX_VALUE, 0L), |
699 |
|
|
false); |
700 |
|
|
} |
701 |
|
|
|
702 |
|
|
/** |
703 |
dl |
1.16 |
* Returns an effectively unlimited stream of pseudorandom {@code |
704 |
|
|
* long} values from this generator and/or one split from it. |
705 |
dl |
1.1 |
* |
706 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
707 |
|
|
* longs(Long.MAX_VALUE)}. |
708 |
|
|
* |
709 |
|
|
* @return a stream of pseudorandom {@code long} values |
710 |
|
|
*/ |
711 |
|
|
public LongStream longs() { |
712 |
|
|
return StreamSupport.longStream |
713 |
|
|
(new RandomLongsSpliterator |
714 |
|
|
(this, 0L, Long.MAX_VALUE, Long.MAX_VALUE, 0L), |
715 |
|
|
false); |
716 |
|
|
} |
717 |
|
|
|
718 |
|
|
/** |
719 |
dl |
1.7 |
* Returns a stream producing the given {@code streamSize} number of |
720 |
dl |
1.18 |
* 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 |
dl |
1.1 |
* |
724 |
|
|
* @param streamSize the number of values to generate |
725 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
726 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
727 |
dl |
1.1 |
* @return a stream of pseudorandom {@code long} values, |
728 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
729 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code streamSize} is |
730 |
dl |
1.7 |
* less than zero, or {@code randomNumberOrigin} |
731 |
dl |
1.1 |
* is greater than or equal to {@code randomNumberBound} |
732 |
|
|
*/ |
733 |
|
|
public LongStream longs(long streamSize, long randomNumberOrigin, |
734 |
|
|
long randomNumberBound) { |
735 |
|
|
if (streamSize < 0L) |
736 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
737 |
dl |
1.1 |
if (randomNumberOrigin >= randomNumberBound) |
738 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
739 |
dl |
1.1 |
return StreamSupport.longStream |
740 |
|
|
(new RandomLongsSpliterator |
741 |
|
|
(this, 0L, streamSize, randomNumberOrigin, randomNumberBound), |
742 |
|
|
false); |
743 |
|
|
} |
744 |
|
|
|
745 |
|
|
/** |
746 |
|
|
* Returns an effectively unlimited stream of pseudorandom {@code |
747 |
dl |
1.18 |
* long} values from this generator and/or one split from it; each value |
748 |
|
|
* conforms to the given origin (inclusive) and bound (exclusive). |
749 |
dl |
1.1 |
* |
750 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
751 |
|
|
* longs(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}. |
752 |
|
|
* |
753 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
754 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
755 |
dl |
1.1 |
* @return a stream of pseudorandom {@code long} values, |
756 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
757 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code randomNumberOrigin} |
758 |
|
|
* is greater than or equal to {@code randomNumberBound} |
759 |
|
|
*/ |
760 |
|
|
public LongStream longs(long randomNumberOrigin, long randomNumberBound) { |
761 |
|
|
if (randomNumberOrigin >= randomNumberBound) |
762 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
763 |
dl |
1.1 |
return StreamSupport.longStream |
764 |
|
|
(new RandomLongsSpliterator |
765 |
|
|
(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound), |
766 |
|
|
false); |
767 |
|
|
} |
768 |
|
|
|
769 |
|
|
/** |
770 |
dl |
1.7 |
* Returns a stream producing the given {@code streamSize} number of |
771 |
dl |
1.18 |
* pseudorandom {@code double} values from this generator and/or one split |
772 |
|
|
* from it; each value is between zero (inclusive) and one (exclusive). |
773 |
dl |
1.1 |
* |
774 |
|
|
* @param streamSize the number of values to generate |
775 |
|
|
* @return a stream of {@code double} values |
776 |
|
|
* @throws IllegalArgumentException if {@code streamSize} is |
777 |
dl |
1.7 |
* less than zero |
778 |
dl |
1.1 |
*/ |
779 |
|
|
public DoubleStream doubles(long streamSize) { |
780 |
|
|
if (streamSize < 0L) |
781 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
782 |
dl |
1.1 |
return StreamSupport.doubleStream |
783 |
|
|
(new RandomDoublesSpliterator |
784 |
|
|
(this, 0L, streamSize, Double.MAX_VALUE, 0.0), |
785 |
|
|
false); |
786 |
|
|
} |
787 |
|
|
|
788 |
|
|
/** |
789 |
|
|
* Returns an effectively unlimited stream of pseudorandom {@code |
790 |
dl |
1.18 |
* double} values from this generator and/or one split from it; each value |
791 |
|
|
* is between zero (inclusive) and one (exclusive). |
792 |
dl |
1.1 |
* |
793 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
794 |
|
|
* doubles(Long.MAX_VALUE)}. |
795 |
|
|
* |
796 |
|
|
* @return a stream of pseudorandom {@code double} values |
797 |
|
|
*/ |
798 |
|
|
public DoubleStream doubles() { |
799 |
|
|
return StreamSupport.doubleStream |
800 |
|
|
(new RandomDoublesSpliterator |
801 |
|
|
(this, 0L, Long.MAX_VALUE, Double.MAX_VALUE, 0.0), |
802 |
|
|
false); |
803 |
|
|
} |
804 |
|
|
|
805 |
|
|
/** |
806 |
dl |
1.7 |
* Returns a stream producing the given {@code streamSize} number of |
807 |
dl |
1.18 |
* 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 |
dl |
1.1 |
* |
811 |
|
|
* @param streamSize the number of values to generate |
812 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
813 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
814 |
dl |
1.1 |
* @return a stream of pseudorandom {@code double} values, |
815 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
816 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code streamSize} is |
817 |
dl |
1.18 |
* less than zero |
818 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code randomNumberOrigin} |
819 |
|
|
* is greater than or equal to {@code randomNumberBound} |
820 |
|
|
*/ |
821 |
|
|
public DoubleStream doubles(long streamSize, double randomNumberOrigin, |
822 |
|
|
double randomNumberBound) { |
823 |
|
|
if (streamSize < 0L) |
824 |
dl |
1.15 |
throw new IllegalArgumentException(BadSize); |
825 |
dl |
1.7 |
if (!(randomNumberOrigin < randomNumberBound)) |
826 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
827 |
dl |
1.1 |
return StreamSupport.doubleStream |
828 |
|
|
(new RandomDoublesSpliterator |
829 |
|
|
(this, 0L, streamSize, randomNumberOrigin, randomNumberBound), |
830 |
|
|
false); |
831 |
|
|
} |
832 |
|
|
|
833 |
|
|
/** |
834 |
|
|
* Returns an effectively unlimited stream of pseudorandom {@code |
835 |
dl |
1.18 |
* double} values from this generator and/or one split from it; each value |
836 |
|
|
* conforms to the given origin (inclusive) and bound (exclusive). |
837 |
dl |
1.1 |
* |
838 |
|
|
* @implNote This method is implemented to be equivalent to {@code |
839 |
|
|
* doubles(Long.MAX_VALUE, randomNumberOrigin, randomNumberBound)}. |
840 |
|
|
* |
841 |
dl |
1.18 |
* @param randomNumberOrigin the origin (inclusive) of each random value |
842 |
|
|
* @param randomNumberBound the bound (exclusive) of each random value |
843 |
dl |
1.1 |
* @return a stream of pseudorandom {@code double} values, |
844 |
dl |
1.18 |
* each with the given origin (inclusive) and bound (exclusive) |
845 |
dl |
1.1 |
* @throws IllegalArgumentException if {@code randomNumberOrigin} |
846 |
|
|
* is greater than or equal to {@code randomNumberBound} |
847 |
|
|
*/ |
848 |
|
|
public DoubleStream doubles(double randomNumberOrigin, double randomNumberBound) { |
849 |
dl |
1.7 |
if (!(randomNumberOrigin < randomNumberBound)) |
850 |
dl |
1.15 |
throw new IllegalArgumentException(BadRange); |
851 |
dl |
1.1 |
return StreamSupport.doubleStream |
852 |
|
|
(new RandomDoublesSpliterator |
853 |
|
|
(this, 0L, Long.MAX_VALUE, randomNumberOrigin, randomNumberBound), |
854 |
|
|
false); |
855 |
|
|
} |
856 |
|
|
|
857 |
|
|
/** |
858 |
|
|
* Spliterator for int streams. We multiplex the four int |
859 |
dl |
1.7 |
* versions into one class by treating a bound less than origin as |
860 |
dl |
1.1 |
* unbounded, and also by treating "infinite" as equivalent to |
861 |
|
|
* Long.MAX_VALUE. For splits, it uses the standard divide-by-two |
862 |
|
|
* approach. The long and double versions of this class are |
863 |
|
|
* identical except for types. |
864 |
|
|
*/ |
865 |
dl |
1.11 |
static final class RandomIntsSpliterator implements Spliterator.OfInt { |
866 |
dl |
1.1 |
final SplittableRandom rng; |
867 |
|
|
long index; |
868 |
|
|
final long fence; |
869 |
|
|
final int origin; |
870 |
|
|
final int bound; |
871 |
|
|
RandomIntsSpliterator(SplittableRandom rng, long index, long fence, |
872 |
|
|
int origin, int bound) { |
873 |
|
|
this.rng = rng; this.index = index; this.fence = fence; |
874 |
|
|
this.origin = origin; this.bound = bound; |
875 |
|
|
} |
876 |
|
|
|
877 |
|
|
public RandomIntsSpliterator trySplit() { |
878 |
|
|
long i = index, m = (i + fence) >>> 1; |
879 |
|
|
return (m <= i) ? null : |
880 |
|
|
new RandomIntsSpliterator(rng.split(), i, index = m, origin, bound); |
881 |
|
|
} |
882 |
|
|
|
883 |
|
|
public long estimateSize() { |
884 |
|
|
return fence - index; |
885 |
|
|
} |
886 |
|
|
|
887 |
|
|
public int characteristics() { |
888 |
|
|
return (Spliterator.SIZED | Spliterator.SUBSIZED | |
889 |
dl |
1.4 |
Spliterator.NONNULL | Spliterator.IMMUTABLE); |
890 |
dl |
1.1 |
} |
891 |
|
|
|
892 |
|
|
public boolean tryAdvance(IntConsumer consumer) { |
893 |
|
|
if (consumer == null) throw new NullPointerException(); |
894 |
|
|
long i = index, f = fence; |
895 |
|
|
if (i < f) { |
896 |
|
|
consumer.accept(rng.internalNextInt(origin, bound)); |
897 |
|
|
index = i + 1; |
898 |
|
|
return true; |
899 |
|
|
} |
900 |
|
|
return false; |
901 |
|
|
} |
902 |
|
|
|
903 |
|
|
public void forEachRemaining(IntConsumer consumer) { |
904 |
|
|
if (consumer == null) throw new NullPointerException(); |
905 |
|
|
long i = index, f = fence; |
906 |
|
|
if (i < f) { |
907 |
|
|
index = f; |
908 |
dl |
1.15 |
SplittableRandom r = rng; |
909 |
dl |
1.1 |
int o = origin, b = bound; |
910 |
|
|
do { |
911 |
dl |
1.15 |
consumer.accept(r.internalNextInt(o, b)); |
912 |
dl |
1.1 |
} while (++i < f); |
913 |
|
|
} |
914 |
|
|
} |
915 |
|
|
} |
916 |
|
|
|
917 |
|
|
/** |
918 |
|
|
* Spliterator for long streams. |
919 |
|
|
*/ |
920 |
dl |
1.11 |
static final class RandomLongsSpliterator implements Spliterator.OfLong { |
921 |
dl |
1.1 |
final SplittableRandom rng; |
922 |
|
|
long index; |
923 |
|
|
final long fence; |
924 |
|
|
final long origin; |
925 |
|
|
final long bound; |
926 |
|
|
RandomLongsSpliterator(SplittableRandom rng, long index, long fence, |
927 |
|
|
long origin, long bound) { |
928 |
|
|
this.rng = rng; this.index = index; this.fence = fence; |
929 |
|
|
this.origin = origin; this.bound = bound; |
930 |
|
|
} |
931 |
|
|
|
932 |
|
|
public RandomLongsSpliterator trySplit() { |
933 |
|
|
long i = index, m = (i + fence) >>> 1; |
934 |
|
|
return (m <= i) ? null : |
935 |
|
|
new RandomLongsSpliterator(rng.split(), i, index = m, origin, bound); |
936 |
|
|
} |
937 |
|
|
|
938 |
|
|
public long estimateSize() { |
939 |
|
|
return fence - index; |
940 |
|
|
} |
941 |
|
|
|
942 |
|
|
public int characteristics() { |
943 |
|
|
return (Spliterator.SIZED | Spliterator.SUBSIZED | |
944 |
dl |
1.4 |
Spliterator.NONNULL | Spliterator.IMMUTABLE); |
945 |
dl |
1.1 |
} |
946 |
|
|
|
947 |
|
|
public boolean tryAdvance(LongConsumer consumer) { |
948 |
|
|
if (consumer == null) throw new NullPointerException(); |
949 |
|
|
long i = index, f = fence; |
950 |
|
|
if (i < f) { |
951 |
|
|
consumer.accept(rng.internalNextLong(origin, bound)); |
952 |
|
|
index = i + 1; |
953 |
|
|
return true; |
954 |
|
|
} |
955 |
|
|
return false; |
956 |
|
|
} |
957 |
|
|
|
958 |
|
|
public void forEachRemaining(LongConsumer consumer) { |
959 |
|
|
if (consumer == null) throw new NullPointerException(); |
960 |
|
|
long i = index, f = fence; |
961 |
|
|
if (i < f) { |
962 |
|
|
index = f; |
963 |
dl |
1.15 |
SplittableRandom r = rng; |
964 |
dl |
1.1 |
long o = origin, b = bound; |
965 |
|
|
do { |
966 |
dl |
1.15 |
consumer.accept(r.internalNextLong(o, b)); |
967 |
dl |
1.1 |
} while (++i < f); |
968 |
|
|
} |
969 |
|
|
} |
970 |
|
|
|
971 |
|
|
} |
972 |
|
|
|
973 |
|
|
/** |
974 |
|
|
* Spliterator for double streams. |
975 |
|
|
*/ |
976 |
dl |
1.11 |
static final class RandomDoublesSpliterator implements Spliterator.OfDouble { |
977 |
dl |
1.1 |
final SplittableRandom rng; |
978 |
|
|
long index; |
979 |
|
|
final long fence; |
980 |
|
|
final double origin; |
981 |
|
|
final double bound; |
982 |
|
|
RandomDoublesSpliterator(SplittableRandom rng, long index, long fence, |
983 |
|
|
double origin, double bound) { |
984 |
|
|
this.rng = rng; this.index = index; this.fence = fence; |
985 |
|
|
this.origin = origin; this.bound = bound; |
986 |
|
|
} |
987 |
|
|
|
988 |
|
|
public RandomDoublesSpliterator trySplit() { |
989 |
|
|
long i = index, m = (i + fence) >>> 1; |
990 |
|
|
return (m <= i) ? null : |
991 |
|
|
new RandomDoublesSpliterator(rng.split(), i, index = m, origin, bound); |
992 |
|
|
} |
993 |
|
|
|
994 |
|
|
public long estimateSize() { |
995 |
|
|
return fence - index; |
996 |
|
|
} |
997 |
|
|
|
998 |
|
|
public int characteristics() { |
999 |
|
|
return (Spliterator.SIZED | Spliterator.SUBSIZED | |
1000 |
dl |
1.4 |
Spliterator.NONNULL | Spliterator.IMMUTABLE); |
1001 |
dl |
1.1 |
} |
1002 |
|
|
|
1003 |
|
|
public boolean tryAdvance(DoubleConsumer consumer) { |
1004 |
|
|
if (consumer == null) throw new NullPointerException(); |
1005 |
|
|
long i = index, f = fence; |
1006 |
|
|
if (i < f) { |
1007 |
|
|
consumer.accept(rng.internalNextDouble(origin, bound)); |
1008 |
|
|
index = i + 1; |
1009 |
|
|
return true; |
1010 |
|
|
} |
1011 |
|
|
return false; |
1012 |
|
|
} |
1013 |
|
|
|
1014 |
|
|
public void forEachRemaining(DoubleConsumer consumer) { |
1015 |
|
|
if (consumer == null) throw new NullPointerException(); |
1016 |
|
|
long i = index, f = fence; |
1017 |
|
|
if (i < f) { |
1018 |
|
|
index = f; |
1019 |
dl |
1.15 |
SplittableRandom r = rng; |
1020 |
dl |
1.1 |
double o = origin, b = bound; |
1021 |
|
|
do { |
1022 |
dl |
1.15 |
consumer.accept(r.internalNextDouble(o, b)); |
1023 |
dl |
1.1 |
} while (++i < f); |
1024 |
|
|
} |
1025 |
|
|
} |
1026 |
|
|
} |
1027 |
|
|
|
1028 |
|
|
} |