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* http://creativecommons.org/publicdomain/zero/1.0/ |
5 |
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*/ |
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|
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import java.util.Arrays; |
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import java.util.ArrayList; |
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import java.util.List; |
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import java.util.SplittableRandom; |
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import java.util.concurrent.atomic.AtomicInteger; |
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import java.util.concurrent.atomic.LongAdder; |
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import java.lang.reflect.Method; |
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import java.util.function.Predicate; |
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import java.util.stream.Collectors; |
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|
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import junit.framework.Test; |
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import junit.framework.TestSuite; |
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assertEquals(size, counter.sum()); |
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} |
533 |
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|
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/** |
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* SplittableRandom should implement most of Random's public methods |
536 |
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*/ |
537 |
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public void testShouldImplementMostRandomMethods() throws Throwable { |
538 |
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Predicate<Method> wasForgotten = method -> { |
539 |
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String name = method.getName(); |
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// some methods deliberately not implemented |
541 |
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if (name.equals("setSeed")) return false; |
542 |
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if (name.equals("nextFloat")) return false; |
543 |
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if (name.equals("nextGaussian")) return false; |
544 |
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try { |
545 |
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SplittableRandom.class.getMethod( |
546 |
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method.getName(), method.getParameterTypes()); |
547 |
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} catch (ReflectiveOperationException ex) { |
548 |
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return true; |
549 |
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} |
550 |
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return false; |
551 |
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}; |
552 |
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List<Method> forgotten = |
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Arrays.stream(java.util.Random.class.getMethods()) |
554 |
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.filter(wasForgotten) |
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.collect(Collectors.toList()); |
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if (!forgotten.isEmpty()) |
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throw new AssertionError("Please implement: " + forgotten); |
558 |
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} |
559 |
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|
560 |
+ |
/** |
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* Repeated calls to nextBytes produce at least values of different signs for every byte |
562 |
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*/ |
563 |
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public void testNextBytes() { |
564 |
+ |
SplittableRandom sr = new SplittableRandom(); |
565 |
+ |
int n = sr.nextInt(20); |
566 |
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byte[] bytes = new byte[n]; |
567 |
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outer: |
568 |
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for (int i = 0; i < n; i++) { |
569 |
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for (int tries = NCALLS; tries-->0; ) { |
570 |
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byte before = bytes[i]; |
571 |
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sr.nextBytes(bytes); |
572 |
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byte after = bytes[i]; |
573 |
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if (after * before < 0) |
574 |
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continue outer; |
575 |
+ |
} |
576 |
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fail("not enough variation in random bytes"); |
577 |
+ |
} |
578 |
+ |
} |
579 |
+ |
|
580 |
|
} |