test/tck/ThreadLocalRandomTest.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */
import junit.framework.*;
import java.util.*;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.atomic.LongAdder;

public class ThreadLocalRandomTest extends JSR166TestCase {

    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());
    }
    public static Test suite() {
        return new TestSuite(ThreadLocalRandomTest.class);
    }

    /*
     * Testing coverage notes:
     *
     * We don't test randomness properties, but only that repeated
     * calls, up to NCALLS tries, produce at least one different
     * result.  For bounded versions, we sample various intervals
     * across multiples of primes.
     */

    // max numbers of calls to detect getting stuck on one value
    static final int NCALLS = 10000;

    // max sampled int bound
    static final int MAX_INT_BOUND = (1 << 28);

    // max sampled long bound
    static final long MAX_LONG_BOUND = (1L << 42);

    // Number of replications for other checks
    static final int REPS = 20;

    /**
     * setSeed throws UnsupportedOperationException
     */
    public void testSetSeed() {
        try {
            ThreadLocalRandom.current().setSeed(17);
            shouldThrow();
        } catch (UnsupportedOperationException success) {}
    }

    /**
     * Repeated calls to nextInt produce at least two distinct results
     */
    public void testNextInt() {
        int f = ThreadLocalRandom.current().nextInt();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextInt() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * Repeated calls to nextLong produce at least two distinct results
     */
    public void testNextLong() {
        long f = ThreadLocalRandom.current().nextLong();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextLong() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * Repeated calls to nextBoolean produce at least two distinct results
     */
    public void testNextBoolean() {
        boolean f = ThreadLocalRandom.current().nextBoolean();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextBoolean() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * Repeated calls to nextFloat produce at least two distinct results
     */
    public void testNextFloat() {
        float f = ThreadLocalRandom.current().nextFloat();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextFloat() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * Repeated calls to nextDouble produce at least two distinct results
     */
    public void testNextDouble() {
        double f = ThreadLocalRandom.current().nextDouble();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextDouble() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * Repeated calls to nextGaussian produce at least two distinct results
     */
    public void testNextGaussian() {
        double f = ThreadLocalRandom.current().nextGaussian();
        int i = 0;
        while (i < NCALLS && ThreadLocalRandom.current().nextGaussian() == f)
            ++i;
        assertTrue(i < NCALLS);
    }

    /**
     * nextInt(negative) throws IllegalArgumentException
     */
    public void testNextIntBoundedNeg() {
        try {
            int f = ThreadLocalRandom.current().nextInt(-17);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * nextInt(least >= bound) throws IllegalArgumentException
     */
    public void testNextIntBadBounds() {
        try {
            int f = ThreadLocalRandom.current().nextInt(17, 2);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * nextInt(bound) returns 0 <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextIntBounded() {
        // sample bound space across prime number increments
        for (int bound = 2; bound < MAX_INT_BOUND; bound += 524959) {
            int f = ThreadLocalRandom.current().nextInt(bound);
            assertTrue(0 <= f && f < bound);
            int i = 0;
            int j;
            while (i < NCALLS &&
                   (j = ThreadLocalRandom.current().nextInt(bound)) == f) {
                assertTrue(0 <= j && j < bound);
                ++i;
            }
            assertTrue(i < NCALLS);
        }
    }

    /**
     * nextInt(least, bound) returns least <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextIntBounded2() {
        for (int least = -15485863; least < MAX_INT_BOUND; least += 524959) {
            for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 49979687) {
                int f = ThreadLocalRandom.current().nextInt(least, bound);
                assertTrue(least <= f && f < bound);
                int i = 0;
                int j;
                while (i < NCALLS &&
                       (j = ThreadLocalRandom.current().nextInt(least, bound)) == f) {
                    assertTrue(least <= j && j < bound);
                    ++i;
                }
                assertTrue(i < NCALLS);
            }
        }
    }

    /**
     * nextLong(negative) throws IllegalArgumentException
     */
    public void testNextLongBoundedNeg() {
        try {
            long f = ThreadLocalRandom.current().nextLong(-17);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * nextLong(least >= bound) throws IllegalArgumentException
     */
    public void testNextLongBadBounds() {
        try {
            long f = ThreadLocalRandom.current().nextLong(17, 2);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * nextLong(bound) returns 0 <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextLongBounded() {
        for (long bound = 2; bound < MAX_LONG_BOUND; bound += 15485863) {
            long f = ThreadLocalRandom.current().nextLong(bound);
            assertTrue(0 <= f && f < bound);
            int i = 0;
            long j;
            while (i < NCALLS &&
                   (j = ThreadLocalRandom.current().nextLong(bound)) == f) {
                assertTrue(0 <= j && j < bound);
                ++i;
            }
            assertTrue(i < NCALLS);
        }
    }

    /**
     * nextLong(least, bound) returns least <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextLongBounded2() {
        for (long least = -86028121; least < MAX_LONG_BOUND; least += 982451653L) {
            for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
                long f = ThreadLocalRandom.current().nextLong(least, bound);
                assertTrue(least <= f && f < bound);
                int i = 0;
                long j;
                while (i < NCALLS &&
                       (j = ThreadLocalRandom.current().nextLong(least, bound)) == f) {
                    assertTrue(least <= j && j < bound);
                    ++i;
                }
                assertTrue(i < NCALLS);
            }
        }
    }

    /**
     * nextDouble(least, bound) returns least <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextDoubleBounded2() {
        for (double least = 0.0001; least < 1.0e20; least *= 8) {
            for (double bound = least * 1.001; bound < 1.0e20; bound *= 16) {
                double f = ThreadLocalRandom.current().nextDouble(least, bound);
                assertTrue(least <= f && f < bound);
                int i = 0;
                double j;
                while (i < NCALLS &&
                       (j = ThreadLocalRandom.current().nextDouble(least, bound)) == f) {
                    assertTrue(least <= j && j < bound);
                    ++i;
                }
                assertTrue(i < NCALLS);
            }
        }
    }

    /**
     * Different threads produce different pseudo-random sequences
     */
    public void testDifferentSequences() {
        // Don't use main thread's ThreadLocalRandom - it is likely to
        // be polluted by previous tests.
        final AtomicReference<ThreadLocalRandom> threadLocalRandom =
            new AtomicReference<ThreadLocalRandom>();
        final AtomicLong rand = new AtomicLong();

        long firstRand = 0;
        ThreadLocalRandom firstThreadLocalRandom = null;

        final CheckedRunnable getRandomState = new CheckedRunnable() {
            public void realRun() {
                ThreadLocalRandom current = ThreadLocalRandom.current();
                assertSame(current, ThreadLocalRandom.current());
                // test bug: the following is not guaranteed and not true in JDK8
                //                assertNotSame(current, threadLocalRandom.get());
                rand.set(current.nextLong());
                threadLocalRandom.set(current);
            }};

        Thread first = newStartedThread(getRandomState);
        awaitTermination(first);
        firstRand = rand.get();
        firstThreadLocalRandom = threadLocalRandom.get();

        for (int i = 0; i < NCALLS; i++) {
            Thread t = newStartedThread(getRandomState);
            awaitTermination(t);
            if (firstRand != rand.get())
                return;
        }
        fail("all threads generate the same pseudo-random sequence");
    }

    /**
     * Invoking sized ints, long, doubles, with negative sizes throws
     * IllegalArgumentException
     */
    public void testBadStreamSize() {
        ThreadLocalRandom r = ThreadLocalRandom.current();
        try {
            java.util.stream.IntStream x = r.ints(-1L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.IntStream x = r.ints(-1L, 2, 3);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.LongStream x = r.longs(-1L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.LongStream x = r.longs(-1L, -1L, 1L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.DoubleStream x = r.doubles(-1L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.DoubleStream x = r.doubles(-1L, .5, .6);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * Invoking bounded ints, long, doubles, with illegal bounds throws
     * IllegalArgumentException
     */
    public void testBadStreamBounds() {
        ThreadLocalRandom r = ThreadLocalRandom.current();
        try {
            java.util.stream.IntStream x = r.ints(2, 1);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.IntStream x = r.ints(10, 42, 42);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.LongStream x = r.longs(-1L, -1L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.LongStream x = r.longs(10, 1L, -2L);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.DoubleStream x = r.doubles(0.0, 0.0);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
        try {
            java.util.stream.DoubleStream x = r.doubles(10, .5, .4);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * A parallel sized stream of ints generates the given number of values
     */
    public void testIntsCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 0;
        for (int reps = 0; reps < REPS; ++reps) {
            counter.reset();
            r.ints(size).parallel().forEach(x -> {counter.increment();});
            assertEquals(size, counter.sum());
            size += 524959;
        }
    }

    /**
     * A parallel sized stream of longs generates the given number of values
     */
    public void testLongsCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 0;
        for (int reps = 0; reps < REPS; ++reps) {
            counter.reset();
            r.longs(size).parallel().forEach(x -> {counter.increment();});
            assertEquals(size, counter.sum());
            size += 524959;
        }
    }

    /**
     * A parallel sized stream of doubles generates the given number of values
     */
    public void testDoublesCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 0;
        for (int reps = 0; reps < REPS; ++reps) {
            counter.reset();
            r.doubles(size).parallel().forEach(x -> {counter.increment();});
            assertEquals(size, counter.sum());
            size += 524959;
        }
    }

    /**
     * Each of a parallel sized stream of bounded ints is within bounds
     */
    public void testBoundedInts() {
        AtomicInteger fails = new AtomicInteger(0);
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 12345L;
        for (int least = -15485867; least < MAX_INT_BOUND; least += 524959) {
            for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 67867967) {
                final int lo = least, hi = bound;
                r.ints(size, lo, hi).parallel().
                    forEach(x -> {if (x < lo || x >= hi)
                                fails.getAndIncrement(); });
            }
        }
        assertEquals(0, fails.get());
    }

    /**
     * Each of a parallel sized stream of bounded longs is within bounds
     */
    public void testBoundedLongs() {
        AtomicInteger fails = new AtomicInteger(0);
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 123L;
        for (long least = -86028121; least < MAX_LONG_BOUND; least += 1982451653L) {
            for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
                final long lo = least, hi = bound;
                r.longs(size, lo, hi).parallel().
                    forEach(x -> {if (x < lo || x >= hi)
                                fails.getAndIncrement(); });
            }
        }
        assertEquals(0, fails.get());
    }

    /**
     * Each of a parallel sized stream of bounded doubles is within bounds
     */
    public void testBoundedDoubles() {
        AtomicInteger fails = new AtomicInteger(0);
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 456;
        for (double least = 0.00011; least < 1.0e20; least *= 9) {
            for (double bound = least * 1.0011; bound < 1.0e20; bound *= 17) {
                final double lo = least, hi = bound;
                r.doubles(size, lo, hi).parallel().
                    forEach(x -> {if (x < lo || x >= hi)
                                fails.getAndIncrement(); });
            }
        }
        assertEquals(0, fails.get());
    }

    /**
     * A parallel unsized stream of ints generates at least 100 values
     */
    public void testUnsizedIntsCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.ints().limit(size).parallel().forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

    /**
     * A parallel unsized stream of longs generates at least 100 values
     */
    public void testUnsizedLongsCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.longs().limit(size).parallel().forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

    /**
     * A parallel unsized stream of doubles generates at least 100 values
     */
    public void testUnsizedDoublesCount() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.doubles().limit(size).parallel().forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

    /**
     * A sequential unsized stream of ints generates at least 100 values
     */
    public void testUnsizedIntsCountSeq() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.ints().limit(size).forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

    /**
     * A sequential unsized stream of longs generates at least 100 values
     */
    public void testUnsizedLongsCountSeq() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.longs().limit(size).forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

    /**
     * A sequential unsized stream of doubles generates at least 100 values
     */
    public void testUnsizedDoublesCountSeq() {
        LongAdder counter = new LongAdder();
        ThreadLocalRandom r = ThreadLocalRandom.current();
        long size = 100;
        r.doubles().limit(size).forEach(x -> {counter.increment();});
        assertEquals(size, counter.sum());
    }

}
Revision:	1.15
Committed:	Wed Aug 14 12:41:18 2013 UTC (10 years, 9 months ago) by dl
Branch:	MAIN
Changes since 1.14:	+234 -0 lines
Log Message:	Add stream tests
#	Content
1	/*
2	* Written by Doug Lea with assistance from members of JCP JSR-166
3	* Expert Group and released to the public domain, as explained at
4	* http://creativecommons.org/publicdomain/zero/1.0/
5	*/
6	import junit.framework.*;
7	import java.util.*;
8	import java.util.concurrent.ThreadLocalRandom;
9	import java.util.concurrent.atomic.AtomicLong;
10	import java.util.concurrent.atomic.AtomicInteger;
11	import java.util.concurrent.atomic.AtomicReference;
12	import java.util.concurrent.atomic.LongAdder;
13
14	public class ThreadLocalRandomTest extends JSR166TestCase {
15
16	public static void main(String[] args) {
17	junit.textui.TestRunner.run(suite());
18	}
19	public static Test suite() {
20	return new TestSuite(ThreadLocalRandomTest.class);
21	}
22
23	/*
24	* Testing coverage notes:
25	*
26	* We don't test randomness properties, but only that repeated
27	* calls, up to NCALLS tries, produce at least one different
28	* result. For bounded versions, we sample various intervals
29	* across multiples of primes.
30	*/
31
32	// max numbers of calls to detect getting stuck on one value
33	static final int NCALLS = 10000;
34
35	// max sampled int bound
36	static final int MAX_INT_BOUND = (1 << 28);
37
38	// max sampled long bound
39	static final long MAX_LONG_BOUND = (1L << 42);
40
41	// Number of replications for other checks
42	static final int REPS = 20;
43
44	/**
45	* setSeed throws UnsupportedOperationException
46	*/
47	public void testSetSeed() {
48	try {
49	ThreadLocalRandom.current().setSeed(17);
50	shouldThrow();
51	} catch (UnsupportedOperationException success) {}
52	}
53
54	/**
55	* Repeated calls to nextInt produce at least two distinct results
56	*/
57	public void testNextInt() {
58	int f = ThreadLocalRandom.current().nextInt();
59	int i = 0;
60	while (i < NCALLS && ThreadLocalRandom.current().nextInt() == f)
61	++i;
62	assertTrue(i < NCALLS);
63	}
64
65	/**
66	* Repeated calls to nextLong produce at least two distinct results
67	*/
68	public void testNextLong() {
69	long f = ThreadLocalRandom.current().nextLong();
70	int i = 0;
71	while (i < NCALLS && ThreadLocalRandom.current().nextLong() == f)
72	++i;
73	assertTrue(i < NCALLS);
74	}
75
76	/**
77	* Repeated calls to nextBoolean produce at least two distinct results
78	*/
79	public void testNextBoolean() {
80	boolean f = ThreadLocalRandom.current().nextBoolean();
81	int i = 0;
82	while (i < NCALLS && ThreadLocalRandom.current().nextBoolean() == f)
83	++i;
84	assertTrue(i < NCALLS);
85	}
86
87	/**
88	* Repeated calls to nextFloat produce at least two distinct results
89	*/
90	public void testNextFloat() {
91	float f = ThreadLocalRandom.current().nextFloat();
92	int i = 0;
93	while (i < NCALLS && ThreadLocalRandom.current().nextFloat() == f)
94	++i;
95	assertTrue(i < NCALLS);
96	}
97
98	/**
99	* Repeated calls to nextDouble produce at least two distinct results
100	*/
101	public void testNextDouble() {
102	double f = ThreadLocalRandom.current().nextDouble();
103	int i = 0;
104	while (i < NCALLS && ThreadLocalRandom.current().nextDouble() == f)
105	++i;
106	assertTrue(i < NCALLS);
107	}
108
109	/**
110	* Repeated calls to nextGaussian produce at least two distinct results
111	*/
112	public void testNextGaussian() {
113	double f = ThreadLocalRandom.current().nextGaussian();
114	int i = 0;
115	while (i < NCALLS && ThreadLocalRandom.current().nextGaussian() == f)
116	++i;
117	assertTrue(i < NCALLS);
118	}
119
120	/**
121	* nextInt(negative) throws IllegalArgumentException
122	*/
123	public void testNextIntBoundedNeg() {
124	try {
125	int f = ThreadLocalRandom.current().nextInt(-17);
126	shouldThrow();
127	} catch (IllegalArgumentException success) {}
128	}
129
130	/**
131	* nextInt(least >= bound) throws IllegalArgumentException
132	*/
133	public void testNextIntBadBounds() {
134	try {
135	int f = ThreadLocalRandom.current().nextInt(17, 2);
136	shouldThrow();
137	} catch (IllegalArgumentException success) {}
138	}
139
140	/**
141	* nextInt(bound) returns 0 <= value < bound;
142	* repeated calls produce at least two distinct results
143	*/
144	public void testNextIntBounded() {
145	// sample bound space across prime number increments
146	for (int bound = 2; bound < MAX_INT_BOUND; bound += 524959) {
147	int f = ThreadLocalRandom.current().nextInt(bound);
148	assertTrue(0 <= f && f < bound);
149	int i = 0;
150	int j;
151	while (i < NCALLS &&
152	(j = ThreadLocalRandom.current().nextInt(bound)) == f) {
153	assertTrue(0 <= j && j < bound);
154	++i;
155	}
156	assertTrue(i < NCALLS);
157	}
158	}
159
160	/**
161	* nextInt(least, bound) returns least <= value < bound;
162	* repeated calls produce at least two distinct results
163	*/
164	public void testNextIntBounded2() {
165	for (int least = -15485863; least < MAX_INT_BOUND; least += 524959) {
166	for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 49979687) {
167	int f = ThreadLocalRandom.current().nextInt(least, bound);
168	assertTrue(least <= f && f < bound);
169	int i = 0;
170	int j;
171	while (i < NCALLS &&
172	(j = ThreadLocalRandom.current().nextInt(least, bound)) == f) {
173	assertTrue(least <= j && j < bound);
174	++i;
175	}
176	assertTrue(i < NCALLS);
177	}
178	}
179	}
180
181	/**
182	* nextLong(negative) throws IllegalArgumentException
183	*/
184	public void testNextLongBoundedNeg() {
185	try {
186	long f = ThreadLocalRandom.current().nextLong(-17);
187	shouldThrow();
188	} catch (IllegalArgumentException success) {}
189	}
190
191	/**
192	* nextLong(least >= bound) throws IllegalArgumentException
193	*/
194	public void testNextLongBadBounds() {
195	try {
196	long f = ThreadLocalRandom.current().nextLong(17, 2);
197	shouldThrow();
198	} catch (IllegalArgumentException success) {}
199	}
200
201	/**
202	* nextLong(bound) returns 0 <= value < bound;
203	* repeated calls produce at least two distinct results
204	*/
205	public void testNextLongBounded() {
206	for (long bound = 2; bound < MAX_LONG_BOUND; bound += 15485863) {
207	long f = ThreadLocalRandom.current().nextLong(bound);
208	assertTrue(0 <= f && f < bound);
209	int i = 0;
210	long j;
211	while (i < NCALLS &&
212	(j = ThreadLocalRandom.current().nextLong(bound)) == f) {
213	assertTrue(0 <= j && j < bound);
214	++i;
215	}
216	assertTrue(i < NCALLS);
217	}
218	}
219
220	/**
221	* nextLong(least, bound) returns least <= value < bound;
222	* repeated calls produce at least two distinct results
223	*/
224	public void testNextLongBounded2() {
225	for (long least = -86028121; least < MAX_LONG_BOUND; least += 982451653L) {
226	for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
227	long f = ThreadLocalRandom.current().nextLong(least, bound);
228	assertTrue(least <= f && f < bound);
229	int i = 0;
230	long j;
231	while (i < NCALLS &&
232	(j = ThreadLocalRandom.current().nextLong(least, bound)) == f) {
233	assertTrue(least <= j && j < bound);
234	++i;
235	}
236	assertTrue(i < NCALLS);
237	}
238	}
239	}
240
241	/**
242	* nextDouble(least, bound) returns least <= value < bound;
243	* repeated calls produce at least two distinct results
244	*/
245	public void testNextDoubleBounded2() {
246	for (double least = 0.0001; least < 1.0e20; least *= 8) {
247	for (double bound = least * 1.001; bound < 1.0e20; bound *= 16) {
248	double f = ThreadLocalRandom.current().nextDouble(least, bound);
249	assertTrue(least <= f && f < bound);
250	int i = 0;
251	double j;
252	while (i < NCALLS &&
253	(j = ThreadLocalRandom.current().nextDouble(least, bound)) == f) {
254	assertTrue(least <= j && j < bound);
255	++i;
256	}
257	assertTrue(i < NCALLS);
258	}
259	}
260	}
261
262	/**
263	* Different threads produce different pseudo-random sequences
264	*/
265	public void testDifferentSequences() {
266	// Don't use main thread's ThreadLocalRandom - it is likely to
267	// be polluted by previous tests.
268	final AtomicReference<ThreadLocalRandom> threadLocalRandom =
269	new AtomicReference<ThreadLocalRandom>();
270	final AtomicLong rand = new AtomicLong();
271
272	long firstRand = 0;
273	ThreadLocalRandom firstThreadLocalRandom = null;
274
275	final CheckedRunnable getRandomState = new CheckedRunnable() {
276	public void realRun() {
277	ThreadLocalRandom current = ThreadLocalRandom.current();
278	assertSame(current, ThreadLocalRandom.current());
279	// test bug: the following is not guaranteed and not true in JDK8
280	// assertNotSame(current, threadLocalRandom.get());
281	rand.set(current.nextLong());
282	threadLocalRandom.set(current);
283	}};
284
285	Thread first = newStartedThread(getRandomState);
286	awaitTermination(first);
287	firstRand = rand.get();
288	firstThreadLocalRandom = threadLocalRandom.get();
289
290	for (int i = 0; i < NCALLS; i++) {
291	Thread t = newStartedThread(getRandomState);
292	awaitTermination(t);
293	if (firstRand != rand.get())
294	return;
295	}
296	fail("all threads generate the same pseudo-random sequence");
297	}
298
299	/**
300	* Invoking sized ints, long, doubles, with negative sizes throws
301	* IllegalArgumentException
302	*/
303	public void testBadStreamSize() {
304	ThreadLocalRandom r = ThreadLocalRandom.current();
305	try {
306	java.util.stream.IntStream x = r.ints(-1L);
307	shouldThrow();
308	} catch (IllegalArgumentException success) {}
309	try {
310	java.util.stream.IntStream x = r.ints(-1L, 2, 3);
311	shouldThrow();
312	} catch (IllegalArgumentException success) {}
313	try {
314	java.util.stream.LongStream x = r.longs(-1L);
315	shouldThrow();
316	} catch (IllegalArgumentException success) {}
317	try {
318	java.util.stream.LongStream x = r.longs(-1L, -1L, 1L);
319	shouldThrow();
320	} catch (IllegalArgumentException success) {}
321	try {
322	java.util.stream.DoubleStream x = r.doubles(-1L);
323	shouldThrow();
324	} catch (IllegalArgumentException success) {}
325	try {
326	java.util.stream.DoubleStream x = r.doubles(-1L, .5, .6);
327	shouldThrow();
328	} catch (IllegalArgumentException success) {}
329	}
330
331	/**
332	* Invoking bounded ints, long, doubles, with illegal bounds throws
333	* IllegalArgumentException
334	*/
335	public void testBadStreamBounds() {
336	ThreadLocalRandom r = ThreadLocalRandom.current();
337	try {
338	java.util.stream.IntStream x = r.ints(2, 1);
339	shouldThrow();
340	} catch (IllegalArgumentException success) {}
341	try {
342	java.util.stream.IntStream x = r.ints(10, 42, 42);
343	shouldThrow();
344	} catch (IllegalArgumentException success) {}
345	try {
346	java.util.stream.LongStream x = r.longs(-1L, -1L);
347	shouldThrow();
348	} catch (IllegalArgumentException success) {}
349	try {
350	java.util.stream.LongStream x = r.longs(10, 1L, -2L);
351	shouldThrow();
352	} catch (IllegalArgumentException success) {}
353	try {
354	java.util.stream.DoubleStream x = r.doubles(0.0, 0.0);
355	shouldThrow();
356	} catch (IllegalArgumentException success) {}
357	try {
358	java.util.stream.DoubleStream x = r.doubles(10, .5, .4);
359	shouldThrow();
360	} catch (IllegalArgumentException success) {}
361	}
362
363	/**
364	* A parallel sized stream of ints generates the given number of values
365	*/
366	public void testIntsCount() {
367	LongAdder counter = new LongAdder();
368	ThreadLocalRandom r = ThreadLocalRandom.current();
369	long size = 0;
370	for (int reps = 0; reps < REPS; ++reps) {
371	counter.reset();
372	r.ints(size).parallel().forEach(x -> {counter.increment();});
373	assertEquals(size, counter.sum());
374	size += 524959;
375	}
376	}
377
378	/**
379	* A parallel sized stream of longs generates the given number of values
380	*/
381	public void testLongsCount() {
382	LongAdder counter = new LongAdder();
383	ThreadLocalRandom r = ThreadLocalRandom.current();
384	long size = 0;
385	for (int reps = 0; reps < REPS; ++reps) {
386	counter.reset();
387	r.longs(size).parallel().forEach(x -> {counter.increment();});
388	assertEquals(size, counter.sum());
389	size += 524959;
390	}
391	}
392
393	/**
394	* A parallel sized stream of doubles generates the given number of values
395	*/
396	public void testDoublesCount() {
397	LongAdder counter = new LongAdder();
398	ThreadLocalRandom r = ThreadLocalRandom.current();
399	long size = 0;
400	for (int reps = 0; reps < REPS; ++reps) {
401	counter.reset();
402	r.doubles(size).parallel().forEach(x -> {counter.increment();});
403	assertEquals(size, counter.sum());
404	size += 524959;
405	}
406	}
407
408	/**
409	* Each of a parallel sized stream of bounded ints is within bounds
410	*/
411	public void testBoundedInts() {
412	AtomicInteger fails = new AtomicInteger(0);
413	ThreadLocalRandom r = ThreadLocalRandom.current();
414	long size = 12345L;
415	for (int least = -15485867; least < MAX_INT_BOUND; least += 524959) {
416	for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 67867967) {
417	final int lo = least, hi = bound;
418	r.ints(size, lo, hi).parallel().
419	forEach(x -> {if (x < lo \|\| x >= hi)
420	fails.getAndIncrement(); });
421	}
422	}
423	assertEquals(0, fails.get());
424	}
425
426	/**
427	* Each of a parallel sized stream of bounded longs is within bounds
428	*/
429	public void testBoundedLongs() {
430	AtomicInteger fails = new AtomicInteger(0);
431	ThreadLocalRandom r = ThreadLocalRandom.current();
432	long size = 123L;
433	for (long least = -86028121; least < MAX_LONG_BOUND; least += 1982451653L) {
434	for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
435	final long lo = least, hi = bound;
436	r.longs(size, lo, hi).parallel().
437	forEach(x -> {if (x < lo \|\| x >= hi)
438	fails.getAndIncrement(); });
439	}
440	}
441	assertEquals(0, fails.get());
442	}
443
444	/**
445	* Each of a parallel sized stream of bounded doubles is within bounds
446	*/
447	public void testBoundedDoubles() {
448	AtomicInteger fails = new AtomicInteger(0);
449	ThreadLocalRandom r = ThreadLocalRandom.current();
450	long size = 456;
451	for (double least = 0.00011; least < 1.0e20; least *= 9) {
452	for (double bound = least * 1.0011; bound < 1.0e20; bound *= 17) {
453	final double lo = least, hi = bound;
454	r.doubles(size, lo, hi).parallel().
455	forEach(x -> {if (x < lo \|\| x >= hi)
456	fails.getAndIncrement(); });
457	}
458	}
459	assertEquals(0, fails.get());
460	}
461
462	/**
463	* A parallel unsized stream of ints generates at least 100 values
464	*/
465	public void testUnsizedIntsCount() {
466	LongAdder counter = new LongAdder();
467	ThreadLocalRandom r = ThreadLocalRandom.current();
468	long size = 100;
469	r.ints().limit(size).parallel().forEach(x -> {counter.increment();});
470	assertEquals(size, counter.sum());
471	}
472
473	/**
474	* A parallel unsized stream of longs generates at least 100 values
475	*/
476	public void testUnsizedLongsCount() {
477	LongAdder counter = new LongAdder();
478	ThreadLocalRandom r = ThreadLocalRandom.current();
479	long size = 100;
480	r.longs().limit(size).parallel().forEach(x -> {counter.increment();});
481	assertEquals(size, counter.sum());
482	}
483
484	/**
485	* A parallel unsized stream of doubles generates at least 100 values
486	*/
487	public void testUnsizedDoublesCount() {
488	LongAdder counter = new LongAdder();
489	ThreadLocalRandom r = ThreadLocalRandom.current();
490	long size = 100;
491	r.doubles().limit(size).parallel().forEach(x -> {counter.increment();});
492	assertEquals(size, counter.sum());
493	}
494
495	/**
496	* A sequential unsized stream of ints generates at least 100 values
497	*/
498	public void testUnsizedIntsCountSeq() {
499	LongAdder counter = new LongAdder();
500	ThreadLocalRandom r = ThreadLocalRandom.current();
501	long size = 100;
502	r.ints().limit(size).forEach(x -> {counter.increment();});
503	assertEquals(size, counter.sum());
504	}
505
506	/**
507	* A sequential unsized stream of longs generates at least 100 values
508	*/
509	public void testUnsizedLongsCountSeq() {
510	LongAdder counter = new LongAdder();
511	ThreadLocalRandom r = ThreadLocalRandom.current();
512	long size = 100;
513	r.longs().limit(size).forEach(x -> {counter.increment();});
514	assertEquals(size, counter.sum());
515	}
516
517	/**
518	* A sequential unsized stream of doubles generates at least 100 values
519	*/
520	public void testUnsizedDoublesCountSeq() {
521	LongAdder counter = new LongAdder();
522	ThreadLocalRandom r = ThreadLocalRandom.current();
523	long size = 100;
524	r.doubles().limit(size).forEach(x -> {counter.increment();});
525	assertEquals(size, counter.sum());
526	}
527
528	}