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