1 /*
   2  * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import org.testng.Assert;
  25 import org.testng.annotations.Test;
  26 
  27 import java.util.SplittableRandom;
  28 import java.util.concurrent.ThreadLocalRandom;
  29 import java.util.concurrent.atomic.AtomicInteger;
  30 import java.util.concurrent.atomic.LongAdder;
  31 import java.util.function.BiConsumer;
  32 
  33 import static org.testng.Assert.assertEquals;
  34 import static org.testng.Assert.assertNotNull;
  35 import static org.testng.AssertJUnit.assertTrue;
  36 
  37 /**
  38  * @test
  39  * @run testng SplittableRandomTest
  40  * @run testng/othervm -Djava.util.secureRandomSeed=true SplittableRandomTest
  41  * @summary test methods on SplittableRandom
  42  * @key randomness
  43  */
  44 @Test
  45 public class SplittableRandomTest {
  46 
  47     // Note: this test was copied from the 166 TCK SplittableRandomTest test
  48     // and modified to be a TestNG test
  49 
  50     /*
  51      * Testing coverage notes:
  52      *
  53      * 1. Many of the test methods are adapted from ThreadLocalRandomTest.
  54      *
  55      * 2. These tests do not check for random number generator quality.
  56      * But we check for minimal API compliance by requiring that
  57      * repeated calls to nextX methods, up to NCALLS tries, produce at
  58      * least two distinct results. (In some possible universe, a
  59      * "correct" implementation might fail, but the odds are vastly
  60      * less than that of encountering a hardware failure while running
  61      * the test.) For bounded nextX methods, we sample various
  62      * intervals across multiples of primes. In other tests, we repeat
  63      * under REPS different values.
  64      */
  65 
  66     // max numbers of calls to detect getting stuck on one value
  67     static final int NCALLS = 10000;
  68 
  69     // max sampled int bound
  70     static final int MAX_INT_BOUND = (1 << 28);
  71 
  72     // max sampled long bound
  73     static final long MAX_LONG_BOUND = (1L << 42);
  74 
  75     // Number of replications for other checks
  76     static final int REPS = 20;
  77 
  78     /**
  79      * Repeated calls to nextInt produce at least two distinct results
  80      */
  81     public void testNextInt() {
  82         SplittableRandom sr = new SplittableRandom();
  83         int f = sr.nextInt();
  84         int i = 0;
  85         while (i < NCALLS && sr.nextInt() == f)
  86             ++i;
  87         assertTrue(i < NCALLS);
  88     }
  89 
  90     /**
  91      * Repeated calls to nextLong produce at least two distinct results
  92      */
  93     public void testNextLong() {
  94         SplittableRandom sr = new SplittableRandom();
  95         long f = sr.nextLong();
  96         int i = 0;
  97         while (i < NCALLS && sr.nextLong() == f)
  98             ++i;
  99         assertTrue(i < NCALLS);
 100     }
 101 
 102     /**
 103      * Repeated calls to nextDouble produce at least two distinct results
 104      */
 105     public void testNextDouble() {
 106         SplittableRandom sr = new SplittableRandom();
 107         double f = sr.nextDouble();
 108         int i = 0;
 109         while (i < NCALLS && sr.nextDouble() == f)
 110             ++i;
 111         assertTrue(i < NCALLS);
 112     }
 113 
 114     /**
 115      * Two SplittableRandoms created with the same seed produce the
 116      * same values for nextLong.
 117      */
 118     public void testSeedConstructor() {
 119         for (long seed = 2; seed < MAX_LONG_BOUND; seed += 15485863)  {
 120             SplittableRandom sr1 = new SplittableRandom(seed);
 121             SplittableRandom sr2 = new SplittableRandom(seed);
 122             for (int i = 0; i < REPS; ++i)
 123                 assertEquals(sr1.nextLong(), sr2.nextLong());
 124         }
 125     }
 126 
 127     /**
 128      * A SplittableRandom produced by split() of a default-constructed
 129      * SplittableRandom generates a different sequence
 130      */
 131     public void testSplit1() {
 132         SplittableRandom sr = new SplittableRandom();
 133         for (int reps = 0; reps < REPS; ++reps) {
 134             SplittableRandom sc = sr.split();
 135             int i = 0;
 136             while (i < NCALLS && sr.nextLong() == sc.nextLong())
 137                 ++i;
 138             assertTrue(i < NCALLS);
 139         }
 140     }
 141 
 142     /**
 143      * A SplittableRandom produced by split() of a seeded-constructed
 144      * SplittableRandom generates a different sequence
 145      */
 146     public void testSplit2() {
 147         SplittableRandom sr = new SplittableRandom(12345);
 148         for (int reps = 0; reps < REPS; ++reps) {
 149             SplittableRandom sc = sr.split();
 150             int i = 0;
 151             while (i < NCALLS && sr.nextLong() == sc.nextLong())
 152                 ++i;
 153             assertTrue(i < NCALLS);
 154         }
 155     }
 156 
 157     /**
 158      * nextInt(negative) throws IllegalArgumentException
 159      */
 160     @Test(expectedExceptions = IllegalArgumentException.class)
 161     public void testNextIntBoundedNeg() {
 162         SplittableRandom sr = new SplittableRandom();
 163         int f = sr.nextInt(-17);
 164     }
 165 
 166     /**
 167      * nextInt(least >= bound) throws IllegalArgumentException
 168      */
 169     @Test(expectedExceptions = IllegalArgumentException.class)
 170     public void testNextIntBadBounds() {
 171         SplittableRandom sr = new SplittableRandom();
 172         int f = sr.nextInt(17, 2);
 173     }
 174 
 175     /**
 176      * nextInt(bound) returns 0 <= value < bound;
 177      * repeated calls produce at least two distinct results
 178      */
 179     public void testNextIntBounded() {
 180         SplittableRandom sr = new SplittableRandom();
 181         // sample bound space across prime number increments
 182         for (int bound = 2; bound < MAX_INT_BOUND; bound += 524959) {
 183             int f = sr.nextInt(bound);
 184             assertTrue(0 <= f && f < bound);
 185             int i = 0;
 186             int j;
 187             while (i < NCALLS &&
 188                    (j = sr.nextInt(bound)) == f) {
 189                 assertTrue(0 <= j && j < bound);
 190                 ++i;
 191             }
 192             assertTrue(i < NCALLS);
 193         }
 194     }
 195 
 196     /**
 197      * nextInt(least, bound) returns least <= value < bound;
 198      * repeated calls produce at least two distinct results
 199      */
 200     public void testNextIntBounded2() {
 201         SplittableRandom sr = new SplittableRandom();
 202         for (int least = -15485863; least < MAX_INT_BOUND; least += 524959) {
 203             for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 49979687) {
 204                 int f = sr.nextInt(least, bound);
 205                 assertTrue(least <= f && f < bound);
 206                 int i = 0;
 207                 int j;
 208                 while (i < NCALLS &&
 209                        (j = sr.nextInt(least, bound)) == f) {
 210                     assertTrue(least <= j && j < bound);
 211                     ++i;
 212                 }
 213                 assertTrue(i < NCALLS);
 214             }
 215         }
 216     }
 217 
 218     /**
 219      * nextLong(negative) throws IllegalArgumentException
 220      */
 221     @Test(expectedExceptions = IllegalArgumentException.class)
 222     public void testNextLongBoundedNeg() {
 223         SplittableRandom sr = new SplittableRandom();
 224         long f = sr.nextLong(-17);
 225     }
 226 
 227     /**
 228      * nextLong(least >= bound) throws IllegalArgumentException
 229      */
 230     @Test(expectedExceptions = IllegalArgumentException.class)
 231     public void testNextLongBadBounds() {
 232         SplittableRandom sr = new SplittableRandom();
 233         long f = sr.nextLong(17, 2);
 234     }
 235 
 236     /**
 237      * nextLong(bound) returns 0 <= value < bound;
 238      * repeated calls produce at least two distinct results
 239      */
 240     public void testNextLongBounded() {
 241         SplittableRandom sr = new SplittableRandom();
 242         for (long bound = 2; bound < MAX_LONG_BOUND; bound += 15485863) {
 243             long f = sr.nextLong(bound);
 244             assertTrue(0 <= f && f < bound);
 245             int i = 0;
 246             long j;
 247             while (i < NCALLS &&
 248                    (j = sr.nextLong(bound)) == f) {
 249                 assertTrue(0 <= j && j < bound);
 250                 ++i;
 251             }
 252             assertTrue(i < NCALLS);
 253         }
 254     }
 255 
 256     /**
 257      * nextLong(least, bound) returns least <= value < bound;
 258      * repeated calls produce at least two distinct results
 259      */
 260     public void testNextLongBounded2() {
 261         SplittableRandom sr = new SplittableRandom();
 262         for (long least = -86028121; least < MAX_LONG_BOUND; least += 982451653L) {
 263             for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
 264                 long f = sr.nextLong(least, bound);
 265                 assertTrue(least <= f && f < bound);
 266                 int i = 0;
 267                 long j;
 268                 while (i < NCALLS &&
 269                        (j = sr.nextLong(least, bound)) == f) {
 270                     assertTrue(least <= j && j < bound);
 271                     ++i;
 272                 }
 273                 assertTrue(i < NCALLS);
 274             }
 275         }
 276     }
 277 
 278     /**
 279      * nextDouble(bound) throws IllegalArgumentException
 280      */
 281     public void testNextDoubleBadBound() {
 282         SplittableRandom sr = new SplittableRandom();
 283         executeAndCatchIAE(() -> sr.nextDouble(0.0));
 284         executeAndCatchIAE(() -> sr.nextDouble(-0.0));
 285         executeAndCatchIAE(() -> sr.nextDouble(+0.0));
 286         executeAndCatchIAE(() -> sr.nextDouble(-1.0));
 287         executeAndCatchIAE(() -> sr.nextDouble(Double.NaN));
 288         executeAndCatchIAE(() -> sr.nextDouble(Double.NEGATIVE_INFINITY));
 289 
 290         // Returns Double.MAX_VALUE
 291 //        executeAndCatchIAE(() -> r.nextDouble(Double.POSITIVE_INFINITY));
 292     }
 293 
 294     /**
 295      * nextDouble(origin, bound) throws IllegalArgumentException
 296      */
 297     public void testNextDoubleBadOriginBound() {
 298         testDoubleBadOriginBound(new SplittableRandom()::nextDouble);
 299     }
 300 
 301     // An arbitrary finite double value
 302     static final double FINITE = Math.PI;
 303 
 304     void testDoubleBadOriginBound(BiConsumer<Double, Double> bi) {
 305         executeAndCatchIAE(() -> bi.accept(17.0, 2.0));
 306         executeAndCatchIAE(() -> bi.accept(0.0, 0.0));
 307         executeAndCatchIAE(() -> bi.accept(Double.NaN, FINITE));
 308         executeAndCatchIAE(() -> bi.accept(FINITE, Double.NaN));
 309         executeAndCatchIAE(() -> bi.accept(Double.NEGATIVE_INFINITY, Double.NEGATIVE_INFINITY));
 310 
 311         // Returns NaN
 312 //        executeAndCatchIAE(() -> bi.accept(Double.NEGATIVE_INFINITY, FINITE));
 313 //        executeAndCatchIAE(() -> bi.accept(Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY));
 314 
 315         executeAndCatchIAE(() -> bi.accept(FINITE, Double.NEGATIVE_INFINITY));
 316 
 317         // Returns Double.MAX_VALUE
 318 //        executeAndCatchIAE(() -> bi.accept(FINITE, Double.POSITIVE_INFINITY));
 319 
 320         executeAndCatchIAE(() -> bi.accept(Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY));
 321         executeAndCatchIAE(() -> bi.accept(Double.POSITIVE_INFINITY, FINITE));
 322         executeAndCatchIAE(() -> bi.accept(Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY));
 323     }
 324 
 325     /**
 326      * nextDouble(least, bound) returns least <= value < bound;
 327      * repeated calls produce at least two distinct results
 328      */
 329     public void testNextDoubleBounded2() {
 330         SplittableRandom sr = new SplittableRandom();
 331         for (double least = 0.0001; least < 1.0e20; least *= 8) {
 332             for (double bound = least * 1.001; bound < 1.0e20; bound *= 16) {
 333                 double f = sr.nextDouble(least, bound);
 334                 assertTrue(least <= f && f < bound);
 335                 int i = 0;
 336                 double j;
 337                 while (i < NCALLS &&
 338                        (j = sr.nextDouble(least, bound)) == f) {
 339                     assertTrue(least <= j && j < bound);
 340                     ++i;
 341                 }
 342                 assertTrue(i < NCALLS);
 343             }
 344         }
 345     }
 346 
 347     /**
 348      * Invoking sized ints, long, doubles, with negative sizes throws
 349      * IllegalArgumentException
 350      */
 351     public void testBadStreamSize() {
 352         SplittableRandom r = new SplittableRandom();
 353         executeAndCatchIAE(() -> r.ints(-1L));
 354         executeAndCatchIAE(() -> r.ints(-1L, 2, 3));
 355         executeAndCatchIAE(() -> r.longs(-1L));
 356         executeAndCatchIAE(() -> r.longs(-1L, -1L, 1L));
 357         executeAndCatchIAE(() -> r.doubles(-1L));
 358         executeAndCatchIAE(() -> r.doubles(-1L, .5, .6));
 359     }
 360 
 361     /**
 362      * Invoking bounded ints, long, doubles, with illegal bounds throws
 363      * IllegalArgumentException
 364      */
 365     public void testBadStreamBounds() {
 366         SplittableRandom r = new SplittableRandom();
 367         executeAndCatchIAE(() -> r.ints(2, 1));
 368         executeAndCatchIAE(() -> r.ints(10, 42, 42));
 369         executeAndCatchIAE(() -> r.longs(-1L, -1L));
 370         executeAndCatchIAE(() -> r.longs(10, 1L, -2L));
 371 
 372         testDoubleBadOriginBound((o, b) -> r.doubles(10, o, b));
 373     }
 374 
 375     private void executeAndCatchIAE(Runnable r) {
 376         executeAndCatch(IllegalArgumentException.class, r);
 377     }
 378 
 379     private void executeAndCatch(Class<? extends Exception> expected, Runnable r) {
 380         Exception caught = null;
 381         try {
 382             r.run();
 383         }
 384         catch (Exception e) {
 385             caught = e;
 386         }
 387 
 388         assertNotNull(caught,
 389                       String.format("No Exception was thrown, expected an Exception of %s to be thrown",
 390                                     expected.getName()));
 391         Assert.assertTrue(expected.isInstance(caught),
 392                           String.format("Exception thrown %s not an instance of %s",
 393                                         caught.getClass().getName(), expected.getName()));
 394     }
 395 
 396     /**
 397      * A parallel sized stream of ints generates the given number of values
 398      */
 399     public void testIntsCount() {
 400         LongAdder counter = new LongAdder();
 401         SplittableRandom r = new SplittableRandom();
 402         long size = 0;
 403         for (int reps = 0; reps < REPS; ++reps) {
 404             counter.reset();
 405             r.ints(size).parallel().forEach(x -> {counter.increment();});
 406             assertEquals(counter.sum(), size);
 407             size += 524959;
 408         }
 409     }
 410 
 411     /**
 412      * A parallel sized stream of longs generates the given number of values
 413      */
 414     public void testLongsCount() {
 415         LongAdder counter = new LongAdder();
 416         SplittableRandom r = new SplittableRandom();
 417         long size = 0;
 418         for (int reps = 0; reps < REPS; ++reps) {
 419             counter.reset();
 420             r.longs(size).parallel().forEach(x -> {counter.increment();});
 421             assertEquals(counter.sum(), size);
 422             size += 524959;
 423         }
 424     }
 425 
 426     /**
 427      * A parallel sized stream of doubles generates the given number of values
 428      */
 429     public void testDoublesCount() {
 430         LongAdder counter = new LongAdder();
 431         SplittableRandom r = new SplittableRandom();
 432         long size = 0;
 433         for (int reps = 0; reps < REPS; ++reps) {
 434             counter.reset();
 435             r.doubles(size).parallel().forEach(x -> {counter.increment();});
 436             assertEquals(counter.sum(), size);
 437             size += 524959;
 438         }
 439     }
 440 
 441     /**
 442      * Each of a parallel sized stream of bounded ints is within bounds
 443      */
 444     public void testBoundedInts() {
 445         AtomicInteger fails = new AtomicInteger(0);
 446         SplittableRandom r = new SplittableRandom();
 447         long size = 12345L;
 448         for (int least = -15485867; least < MAX_INT_BOUND; least += 524959) {
 449             for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 67867967) {
 450                 final int lo = least, hi = bound;
 451                 r.ints(size, lo, hi).parallel().
 452                     forEach(x -> {if (x < lo || x >= hi)
 453                                 fails.getAndIncrement(); });
 454             }
 455         }
 456         assertEquals(fails.get(), 0);
 457     }
 458 
 459     /**
 460      * Each of a parallel sized stream of bounded longs is within bounds
 461      */
 462     public void testBoundedLongs() {
 463         AtomicInteger fails = new AtomicInteger(0);
 464         SplittableRandom r = new SplittableRandom();
 465         long size = 123L;
 466         for (long least = -86028121; least < MAX_LONG_BOUND; least += 1982451653L) {
 467             for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
 468                 final long lo = least, hi = bound;
 469                 r.longs(size, lo, hi).parallel().
 470                     forEach(x -> {if (x < lo || x >= hi)
 471                                 fails.getAndIncrement(); });
 472             }
 473         }
 474         assertEquals(fails.get(), 0);
 475     }
 476 
 477     /**
 478      * Each of a parallel sized stream of bounded doubles is within bounds
 479      */
 480     public void testBoundedDoubles() {
 481         AtomicInteger fails = new AtomicInteger(0);
 482         SplittableRandom r = new SplittableRandom();
 483         long size = 456;
 484         for (double least = 0.00011; least < 1.0e20; least *= 9) {
 485             for (double bound = least * 1.0011; bound < 1.0e20; bound *= 17) {
 486                 final double lo = least, hi = bound;
 487                 r.doubles(size, lo, hi).parallel().
 488                     forEach(x -> {if (x < lo || x >= hi)
 489                                 fails.getAndIncrement(); });
 490             }
 491         }
 492         assertEquals(fails.get(), 0);
 493     }
 494 
 495     /**
 496      * A parallel unsized stream of ints generates at least 100 values
 497      */
 498     public void testUnsizedIntsCount() {
 499         LongAdder counter = new LongAdder();
 500         SplittableRandom r = new SplittableRandom();
 501         long size = 100;
 502         r.ints().limit(size).parallel().forEach(x -> {counter.increment();});
 503         assertEquals(counter.sum(), size);
 504     }
 505 
 506     /**
 507      * A parallel unsized stream of longs generates at least 100 values
 508      */
 509     public void testUnsizedLongsCount() {
 510         LongAdder counter = new LongAdder();
 511         SplittableRandom r = new SplittableRandom();
 512         long size = 100;
 513         r.longs().limit(size).parallel().forEach(x -> {counter.increment();});
 514         assertEquals(counter.sum(), size);
 515     }
 516 
 517     /**
 518      * A parallel unsized stream of doubles generates at least 100 values
 519      */
 520     public void testUnsizedDoublesCount() {
 521         LongAdder counter = new LongAdder();
 522         SplittableRandom r = new SplittableRandom();
 523         long size = 100;
 524         r.doubles().limit(size).parallel().forEach(x -> {counter.increment();});
 525         assertEquals(counter.sum(), size);
 526     }
 527 
 528     /**
 529      * A sequential unsized stream of ints generates at least 100 values
 530      */
 531     public void testUnsizedIntsCountSeq() {
 532         LongAdder counter = new LongAdder();
 533         SplittableRandom r = new SplittableRandom();
 534         long size = 100;
 535         r.ints().limit(size).forEach(x -> {counter.increment();});
 536         assertEquals(counter.sum(), size);
 537     }
 538 
 539     /**
 540      * A sequential unsized stream of longs generates at least 100 values
 541      */
 542     public void testUnsizedLongsCountSeq() {
 543         LongAdder counter = new LongAdder();
 544         SplittableRandom r = new SplittableRandom();
 545         long size = 100;
 546         r.longs().limit(size).forEach(x -> {counter.increment();});
 547         assertEquals(counter.sum(), size);
 548     }
 549 
 550     /**
 551      * A sequential unsized stream of doubles generates at least 100 values
 552      */
 553     public void testUnsizedDoublesCountSeq() {
 554         LongAdder counter = new LongAdder();
 555         SplittableRandom r = new SplittableRandom();
 556         long size = 100;
 557         r.doubles().limit(size).forEach(x -> {counter.increment();});
 558         assertEquals(counter.sum(), size);
 559     }
 560 
 561 }
--- EOF ---