test/tck/SplittableRandomTest.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 java.util.SplittableRandom;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.LongAdder;

import junit.framework.Test;
import junit.framework.TestSuite;

public class SplittableRandomTest extends JSR166TestCase {

    public static void main(String[] args) {
        main(suite(), args);
    }
    public static Test suite() {
        return new TestSuite(SplittableRandomTest.class);
    }

    /*
     * Testing coverage notes:
     *
     * 1. Many of the test methods are adapted from ThreadLocalRandomTest.
     *
     * 2. These tests do not check for random number generator quality.
     * But we check for minimal API compliance by requiring that
     * repeated calls to nextX methods, up to NCALLS tries, produce at
     * least two distinct results. (In some possible universe, a
     * "correct" implementation might fail, but the odds are vastly
     * less than that of encountering a hardware failure while running
     * the test.) For bounded nextX methods, we sample various
     * intervals across multiples of primes. In other tests, we repeat
     * under REPS different values.
     */

    // 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 << 26);

    // max sampled long bound
    static final long MAX_LONG_BOUND = (1L << 40);

    // Number of replications for other checks
    static final int REPS =
        Integer.getInteger("SplittableRandomTest.reps", 4);

    /**
     * Repeated calls to next (only accessible via reflection) produce
     * at least two distinct results, and repeated calls produce all
     * possible values.
     */
    public void testNext() throws ReflectiveOperationException {
        SplittableRandom rnd = new SplittableRandom();
        try {
            java.lang.reflect.Method m
                = SplittableRandom.class.getDeclaredMethod(
                    "next", new Class[] { int.class });
            m.setAccessible(true);

            int i;
            {
                int val = new java.util.Random().nextInt(4);
                for (i = 0; i < NCALLS; i++) {
                    int q = (int) m.invoke(rnd, new Object[] { 2 });
                    if (val == q) break;
                }
                assertTrue(i < NCALLS);
            }

            {
                int r = (int) m.invoke(rnd, new Object[] { 3 });
                for (i = 0; i < NCALLS; i++) {
                    int q = (int) m.invoke(rnd, new Object[] { 3 });
                    assertTrue(q < (1<<3));
                    if (r != q) break;
                }
                assertTrue(i < NCALLS);
            }
        } catch (SecurityException acceptable) {}
    }

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

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

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

    /**
     * Two SplittableRandoms created with the same seed produce the
     * same values for nextLong.
     */
    public void testSeedConstructor() {
        for (long seed = 2; seed < MAX_LONG_BOUND; seed += 15485863) {
            SplittableRandom sr1 = new SplittableRandom(seed);
            SplittableRandom sr2 = new SplittableRandom(seed);
            for (int i = 0; i < REPS; ++i)
                assertEquals(sr1.nextLong(), sr2.nextLong());
        }
    }

    /**
     * A SplittableRandom produced by split() of a default-constructed
     * SplittableRandom generates a different sequence
     */
    public void testSplit1() {
        SplittableRandom sr = new SplittableRandom();
        for (int reps = 0; reps < REPS; ++reps) {
            SplittableRandom sc = sr.split();
            int i = 0;
            while (i < NCALLS && sr.nextLong() == sc.nextLong())
                ++i;
            assertTrue(i < NCALLS);
        }
    }

    /**
     * A SplittableRandom produced by split() of a seeded-constructed
     * SplittableRandom generates a different sequence
     */
    public void testSplit2() {
        SplittableRandom sr = new SplittableRandom(12345);
        for (int reps = 0; reps < REPS; ++reps) {
            SplittableRandom sc = sr.split();
            int i = 0;
            while (i < NCALLS && sr.nextLong() == sc.nextLong())
                ++i;
            assertTrue(i < NCALLS);
        }
    }

    /**
     * nextInt(non-positive) throws IllegalArgumentException
     */
    public void testNextIntBoundNonPositive() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextInt(-17),
            () -> sr.nextInt(0),
            () -> sr.nextInt(Integer.MIN_VALUE),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * nextInt(least >= bound) throws IllegalArgumentException
     */
    public void testNextIntBadBounds() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextInt(17, 2),
            () -> sr.nextInt(-42, -42),
            () -> sr.nextInt(Integer.MAX_VALUE, Integer.MIN_VALUE),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * nextInt(bound) returns 0 <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextIntBounded() {
        SplittableRandom sr = new SplittableRandom();
        for (int i = 0; i < 2; i++) assertEquals(0, sr.nextInt(1));
        // sample bound space across prime number increments
        for (int bound = 2; bound < MAX_INT_BOUND; bound += 524959) {
            int f = sr.nextInt(bound);
            assertTrue(0 <= f && f < bound);
            int i = 0;
            int j;
            while (i < NCALLS &&
                   (j = sr.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() {
        SplittableRandom sr = new SplittableRandom();
        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 = sr.nextInt(least, bound);
                assertTrue(least <= f && f < bound);
                int i = 0;
                int j;
                while (i < NCALLS &&
                       (j = sr.nextInt(least, bound)) == f) {
                    assertTrue(least <= j && j < bound);
                    ++i;
                }
                assertTrue(i < NCALLS);
            }
        }
    }

    /**
     * nextLong(non-positive) throws IllegalArgumentException
     */
    public void testNextLongBoundNonPositive() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextLong(-17L),
            () -> sr.nextLong(0L),
            () -> sr.nextLong(Long.MIN_VALUE),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * nextLong(least >= bound) throws IllegalArgumentException
     */
    public void testNextLongBadBounds() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextLong(17L, 2L),
            () -> sr.nextLong(-42L, -42L),
            () -> sr.nextLong(Long.MAX_VALUE, Long.MIN_VALUE),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * nextLong(bound) returns 0 <= value < bound;
     * repeated calls produce at least two distinct results
     */
    public void testNextLongBounded() {
        SplittableRandom sr = new SplittableRandom();
        for (int i = 0; i < 2; i++) assertEquals(0L, sr.nextLong(1L));
        for (long bound = 2; bound < MAX_LONG_BOUND; bound += 15485863) {
            long f = sr.nextLong(bound);
            assertTrue(0 <= f && f < bound);
            int i = 0;
            long j;
            while (i < NCALLS &&
                   (j = sr.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() {
        SplittableRandom sr = new SplittableRandom();
        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 = sr.nextLong(least, bound);
                assertTrue(least <= f && f < bound);
                int i = 0;
                long j;
                while (i < NCALLS &&
                       (j = sr.nextLong(least, bound)) == f) {
                    assertTrue(least <= j && j < bound);
                    ++i;
                }
                assertTrue(i < NCALLS);
            }
        }
    }

    /**
     * nextDouble(non-positive) throws IllegalArgumentException
     */
    public void testNextDoubleBoundNonPositive() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextDouble(-17.0d),
            () -> sr.nextDouble(0.0d),
            () -> sr.nextDouble(-Double.MIN_VALUE),
            () -> sr.nextDouble(Double.NEGATIVE_INFINITY),
            () -> sr.nextDouble(Double.NaN),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * nextDouble(! (least < bound)) throws IllegalArgumentException
     */
    public void testNextDoubleBadBounds() {
        SplittableRandom sr = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> sr.nextDouble(17.0d, 2.0d),
            () -> sr.nextDouble(-42.0d, -42.0d),
            () -> sr.nextDouble(Double.MAX_VALUE, Double.MIN_VALUE),
            () -> sr.nextDouble(Double.NaN, 0.0d),
            () -> sr.nextDouble(0.0d, Double.NaN),
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    // TODO: Test infinite bounds!
    //() -> sr.nextDouble(Double.NEGATIVE_INFINITY, 0.0d),
    //() -> sr.nextDouble(0.0d, Double.POSITIVE_INFINITY),

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

    /**
     * Invoking sized ints, long, doubles, with negative sizes throws
     * IllegalArgumentException
     */
    public void testBadStreamSize() {
        SplittableRandom r = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> { java.util.stream.IntStream x = r.ints(-1L); },
            () -> { java.util.stream.IntStream x = r.ints(-1L, 2, 3); },
            () -> { java.util.stream.LongStream x = r.longs(-1L); },
            () -> { java.util.stream.LongStream x = r.longs(-1L, -1L, 1L); },
            () -> { java.util.stream.DoubleStream x = r.doubles(-1L); },
            () -> { java.util.stream.DoubleStream x = r.doubles(-1L, .5, .6); },
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * Invoking bounded ints, long, doubles, with illegal bounds throws
     * IllegalArgumentException
     */
    public void testBadStreamBounds() {
        SplittableRandom r = new SplittableRandom();
        Runnable[] throwingActions = {
            () -> { java.util.stream.IntStream x = r.ints(2, 1); },
            () -> { java.util.stream.IntStream x = r.ints(10, 42, 42); },
            () -> { java.util.stream.LongStream x = r.longs(-1L, -1L); },
            () -> { java.util.stream.LongStream x = r.longs(10, 1L, -2L); },
            () -> { java.util.stream.DoubleStream x = r.doubles(0.0, 0.0); },
            () -> { java.util.stream.DoubleStream x = r.doubles(10, .5, .4); },
        };
        assertThrows(IllegalArgumentException.class, throwingActions);
    }

    /**
     * A parallel sized stream of ints generates the given number of values
     */
    public void testIntsCount() {
        LongAdder counter = new LongAdder();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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);
        SplittableRandom r = new SplittableRandom();
        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);
        SplittableRandom r = new SplittableRandom();
        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);
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        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();
        SplittableRandom r = new SplittableRandom();
        long size = 100;
        r.doubles().limit(size).forEach(x -> counter.increment());
        assertEquals(size, counter.sum());
    }

}
Revision:	1.20
Committed:	Sun Nov 13 03:36:50 2016 UTC (7 years, 6 months ago) by jsr166
Branch:	MAIN
Changes since 1.19:	+35 -0 lines
Log Message:	revise (uselessly inaccessible) next(int) method javadoc, implementation and 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
7	import java.util.SplittableRandom;
8	import java.util.concurrent.atomic.AtomicInteger;
9	import java.util.concurrent.atomic.LongAdder;
10
11	import junit.framework.Test;
12	import junit.framework.TestSuite;
13
14	public class SplittableRandomTest extends JSR166TestCase {
15
16	public static void main(String[] args) {
17	main(suite(), args);
18	}
19	public static Test suite() {
20	return new TestSuite(SplittableRandomTest.class);
21	}
22
23	/*
24	* Testing coverage notes:
25	*
26	* 1. Many of the test methods are adapted from ThreadLocalRandomTest.
27	*
28	* 2. These tests do not check for random number generator quality.
29	* But we check for minimal API compliance by requiring that
30	* repeated calls to nextX methods, up to NCALLS tries, produce at
31	* least two distinct results. (In some possible universe, a
32	* "correct" implementation might fail, but the odds are vastly
33	* less than that of encountering a hardware failure while running
34	* the test.) For bounded nextX methods, we sample various
35	* intervals across multiples of primes. In other tests, we repeat
36	* under REPS different values.
37	*/
38
39	// max numbers of calls to detect getting stuck on one value
40	static final int NCALLS = 10000;
41
42	// max sampled int bound
43	static final int MAX_INT_BOUND = (1 << 26);
44
45	// max sampled long bound
46	static final long MAX_LONG_BOUND = (1L << 40);
47
48	// Number of replications for other checks
49	static final int REPS =
50	Integer.getInteger("SplittableRandomTest.reps", 4);
51
52	/**
53	* Repeated calls to next (only accessible via reflection) produce
54	* at least two distinct results, and repeated calls produce all
55	* possible values.
56	*/
57	public void testNext() throws ReflectiveOperationException {
58	SplittableRandom rnd = new SplittableRandom();
59	try {
60	java.lang.reflect.Method m
61	= SplittableRandom.class.getDeclaredMethod(
62	"next", new Class[] { int.class });
63	m.setAccessible(true);
64
65	int i;
66	{
67	int val = new java.util.Random().nextInt(4);
68	for (i = 0; i < NCALLS; i++) {
69	int q = (int) m.invoke(rnd, new Object[] { 2 });
70	if (val == q) break;
71	}
72	assertTrue(i < NCALLS);
73	}
74
75	{
76	int r = (int) m.invoke(rnd, new Object[] { 3 });
77	for (i = 0; i < NCALLS; i++) {
78	int q = (int) m.invoke(rnd, new Object[] { 3 });
79	assertTrue(q < (1<<3));
80	if (r != q) break;
81	}
82	assertTrue(i < NCALLS);
83	}
84	} catch (SecurityException acceptable) {}
85	}
86
87	/**
88	* Repeated calls to nextInt produce at least two distinct results
89	*/
90	public void testNextInt() {
91	SplittableRandom sr = new SplittableRandom();
92	int f = sr.nextInt();
93	int i = 0;
94	while (i < NCALLS && sr.nextInt() == f)
95	++i;
96	assertTrue(i < NCALLS);
97	}
98
99	/**
100	* Repeated calls to nextLong produce at least two distinct results
101	*/
102	public void testNextLong() {
103	SplittableRandom sr = new SplittableRandom();
104	long f = sr.nextLong();
105	int i = 0;
106	while (i < NCALLS && sr.nextLong() == f)
107	++i;
108	assertTrue(i < NCALLS);
109	}
110
111	/**
112	* Repeated calls to nextDouble produce at least two distinct results
113	*/
114	public void testNextDouble() {
115	SplittableRandom sr = new SplittableRandom();
116	double f = sr.nextDouble();
117	int i = 0;
118	while (i < NCALLS && sr.nextDouble() == f)
119	++i;
120	assertTrue(i < NCALLS);
121	}
122
123	/**
124	* Two SplittableRandoms created with the same seed produce the
125	* same values for nextLong.
126	*/
127	public void testSeedConstructor() {
128	for (long seed = 2; seed < MAX_LONG_BOUND; seed += 15485863) {
129	SplittableRandom sr1 = new SplittableRandom(seed);
130	SplittableRandom sr2 = new SplittableRandom(seed);
131	for (int i = 0; i < REPS; ++i)
132	assertEquals(sr1.nextLong(), sr2.nextLong());
133	}
134	}
135
136	/**
137	* A SplittableRandom produced by split() of a default-constructed
138	* SplittableRandom generates a different sequence
139	*/
140	public void testSplit1() {
141	SplittableRandom sr = new SplittableRandom();
142	for (int reps = 0; reps < REPS; ++reps) {
143	SplittableRandom sc = sr.split();
144	int i = 0;
145	while (i < NCALLS && sr.nextLong() == sc.nextLong())
146	++i;
147	assertTrue(i < NCALLS);
148	}
149	}
150
151	/**
152	* A SplittableRandom produced by split() of a seeded-constructed
153	* SplittableRandom generates a different sequence
154	*/
155	public void testSplit2() {
156	SplittableRandom sr = new SplittableRandom(12345);
157	for (int reps = 0; reps < REPS; ++reps) {
158	SplittableRandom sc = sr.split();
159	int i = 0;
160	while (i < NCALLS && sr.nextLong() == sc.nextLong())
161	++i;
162	assertTrue(i < NCALLS);
163	}
164	}
165
166	/**
167	* nextInt(non-positive) throws IllegalArgumentException
168	*/
169	public void testNextIntBoundNonPositive() {
170	SplittableRandom sr = new SplittableRandom();
171	Runnable[] throwingActions = {
172	() -> sr.nextInt(-17),
173	() -> sr.nextInt(0),
174	() -> sr.nextInt(Integer.MIN_VALUE),
175	};
176	assertThrows(IllegalArgumentException.class, throwingActions);
177	}
178
179	/**
180	* nextInt(least >= bound) throws IllegalArgumentException
181	*/
182	public void testNextIntBadBounds() {
183	SplittableRandom sr = new SplittableRandom();
184	Runnable[] throwingActions = {
185	() -> sr.nextInt(17, 2),
186	() -> sr.nextInt(-42, -42),
187	() -> sr.nextInt(Integer.MAX_VALUE, Integer.MIN_VALUE),
188	};
189	assertThrows(IllegalArgumentException.class, throwingActions);
190	}
191
192	/**
193	* nextInt(bound) returns 0 <= value < bound;
194	* repeated calls produce at least two distinct results
195	*/
196	public void testNextIntBounded() {
197	SplittableRandom sr = new SplittableRandom();
198	for (int i = 0; i < 2; i++) assertEquals(0, sr.nextInt(1));
199	// sample bound space across prime number increments
200	for (int bound = 2; bound < MAX_INT_BOUND; bound += 524959) {
201	int f = sr.nextInt(bound);
202	assertTrue(0 <= f && f < bound);
203	int i = 0;
204	int j;
205	while (i < NCALLS &&
206	(j = sr.nextInt(bound)) == f) {
207	assertTrue(0 <= j && j < bound);
208	++i;
209	}
210	assertTrue(i < NCALLS);
211	}
212	}
213
214	/**
215	* nextInt(least, bound) returns least <= value < bound;
216	* repeated calls produce at least two distinct results
217	*/
218	public void testNextIntBounded2() {
219	SplittableRandom sr = new SplittableRandom();
220	for (int least = -15485863; least < MAX_INT_BOUND; least += 524959) {
221	for (int bound = least + 2; bound > least && bound < MAX_INT_BOUND; bound += 49979687) {
222	int f = sr.nextInt(least, bound);
223	assertTrue(least <= f && f < bound);
224	int i = 0;
225	int j;
226	while (i < NCALLS &&
227	(j = sr.nextInt(least, bound)) == f) {
228	assertTrue(least <= j && j < bound);
229	++i;
230	}
231	assertTrue(i < NCALLS);
232	}
233	}
234	}
235
236	/**
237	* nextLong(non-positive) throws IllegalArgumentException
238	*/
239	public void testNextLongBoundNonPositive() {
240	SplittableRandom sr = new SplittableRandom();
241	Runnable[] throwingActions = {
242	() -> sr.nextLong(-17L),
243	() -> sr.nextLong(0L),
244	() -> sr.nextLong(Long.MIN_VALUE),
245	};
246	assertThrows(IllegalArgumentException.class, throwingActions);
247	}
248
249	/**
250	* nextLong(least >= bound) throws IllegalArgumentException
251	*/
252	public void testNextLongBadBounds() {
253	SplittableRandom sr = new SplittableRandom();
254	Runnable[] throwingActions = {
255	() -> sr.nextLong(17L, 2L),
256	() -> sr.nextLong(-42L, -42L),
257	() -> sr.nextLong(Long.MAX_VALUE, Long.MIN_VALUE),
258	};
259	assertThrows(IllegalArgumentException.class, throwingActions);
260	}
261
262	/**
263	* nextLong(bound) returns 0 <= value < bound;
264	* repeated calls produce at least two distinct results
265	*/
266	public void testNextLongBounded() {
267	SplittableRandom sr = new SplittableRandom();
268	for (int i = 0; i < 2; i++) assertEquals(0L, sr.nextLong(1L));
269	for (long bound = 2; bound < MAX_LONG_BOUND; bound += 15485863) {
270	long f = sr.nextLong(bound);
271	assertTrue(0 <= f && f < bound);
272	int i = 0;
273	long j;
274	while (i < NCALLS &&
275	(j = sr.nextLong(bound)) == f) {
276	assertTrue(0 <= j && j < bound);
277	++i;
278	}
279	assertTrue(i < NCALLS);
280	}
281	}
282
283	/**
284	* nextLong(least, bound) returns least <= value < bound;
285	* repeated calls produce at least two distinct results
286	*/
287	public void testNextLongBounded2() {
288	SplittableRandom sr = new SplittableRandom();
289	for (long least = -86028121; least < MAX_LONG_BOUND; least += 982451653L) {
290	for (long bound = least + 2; bound > least && bound < MAX_LONG_BOUND; bound += Math.abs(bound * 7919)) {
291	long f = sr.nextLong(least, bound);
292	assertTrue(least <= f && f < bound);
293	int i = 0;
294	long j;
295	while (i < NCALLS &&
296	(j = sr.nextLong(least, bound)) == f) {
297	assertTrue(least <= j && j < bound);
298	++i;
299	}
300	assertTrue(i < NCALLS);
301	}
302	}
303	}
304
305	/**
306	* nextDouble(non-positive) throws IllegalArgumentException
307	*/
308	public void testNextDoubleBoundNonPositive() {
309	SplittableRandom sr = new SplittableRandom();
310	Runnable[] throwingActions = {
311	() -> sr.nextDouble(-17.0d),
312	() -> sr.nextDouble(0.0d),
313	() -> sr.nextDouble(-Double.MIN_VALUE),
314	() -> sr.nextDouble(Double.NEGATIVE_INFINITY),
315	() -> sr.nextDouble(Double.NaN),
316	};
317	assertThrows(IllegalArgumentException.class, throwingActions);
318	}
319
320	/**
321	* nextDouble(! (least < bound)) throws IllegalArgumentException
322	*/
323	public void testNextDoubleBadBounds() {
324	SplittableRandom sr = new SplittableRandom();
325	Runnable[] throwingActions = {
326	() -> sr.nextDouble(17.0d, 2.0d),
327	() -> sr.nextDouble(-42.0d, -42.0d),
328	() -> sr.nextDouble(Double.MAX_VALUE, Double.MIN_VALUE),
329	() -> sr.nextDouble(Double.NaN, 0.0d),
330	() -> sr.nextDouble(0.0d, Double.NaN),
331	};
332	assertThrows(IllegalArgumentException.class, throwingActions);
333	}
334
335	// TODO: Test infinite bounds!
336	//() -> sr.nextDouble(Double.NEGATIVE_INFINITY, 0.0d),
337	//() -> sr.nextDouble(0.0d, Double.POSITIVE_INFINITY),
338
339	/**
340	* nextDouble(least, bound) returns least <= value < bound;
341	* repeated calls produce at least two distinct results
342	*/
343	public void testNextDoubleBounded2() {
344	SplittableRandom sr = new SplittableRandom();
345	for (double least = 0.0001; least < 1.0e20; least *= 8) {
346	for (double bound = least * 1.001; bound < 1.0e20; bound *= 16) {
347	double f = sr.nextDouble(least, bound);
348	assertTrue(least <= f && f < bound);
349	int i = 0;
350	double j;
351	while (i < NCALLS &&
352	(j = sr.nextDouble(least, bound)) == f) {
353	assertTrue(least <= j && j < bound);
354	++i;
355	}
356	assertTrue(i < NCALLS);
357	}
358	}
359	}
360
361	/**
362	* Invoking sized ints, long, doubles, with negative sizes throws
363	* IllegalArgumentException
364	*/
365	public void testBadStreamSize() {
366	SplittableRandom r = new SplittableRandom();
367	Runnable[] throwingActions = {
368	() -> { java.util.stream.IntStream x = r.ints(-1L); },
369	() -> { java.util.stream.IntStream x = r.ints(-1L, 2, 3); },
370	() -> { java.util.stream.LongStream x = r.longs(-1L); },
371	() -> { java.util.stream.LongStream x = r.longs(-1L, -1L, 1L); },
372	() -> { java.util.stream.DoubleStream x = r.doubles(-1L); },
373	() -> { java.util.stream.DoubleStream x = r.doubles(-1L, .5, .6); },
374	};
375	assertThrows(IllegalArgumentException.class, throwingActions);
376	}
377
378	/**
379	* Invoking bounded ints, long, doubles, with illegal bounds throws
380	* IllegalArgumentException
381	*/
382	public void testBadStreamBounds() {
383	SplittableRandom r = new SplittableRandom();
384	Runnable[] throwingActions = {
385	() -> { java.util.stream.IntStream x = r.ints(2, 1); },
386	() -> { java.util.stream.IntStream x = r.ints(10, 42, 42); },
387	() -> { java.util.stream.LongStream x = r.longs(-1L, -1L); },
388	() -> { java.util.stream.LongStream x = r.longs(10, 1L, -2L); },
389	() -> { java.util.stream.DoubleStream x = r.doubles(0.0, 0.0); },
390	() -> { java.util.stream.DoubleStream x = r.doubles(10, .5, .4); },
391	};
392	assertThrows(IllegalArgumentException.class, throwingActions);
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(size, counter.sum());
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(size, counter.sum());
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(size, counter.sum());
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().forEach(
451	x -> {
452	if (x < lo \|\| x >= hi)
453	fails.getAndIncrement(); });
454	}
455	}
456	assertEquals(0, fails.get());
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().forEach(
470	x -> {
471	if (x < lo \|\| x >= hi)
472	fails.getAndIncrement(); });
473	}
474	}
475	assertEquals(0, fails.get());
476	}
477
478	/**
479	* Each of a parallel sized stream of bounded doubles is within bounds
480	*/
481	public void testBoundedDoubles() {
482	AtomicInteger fails = new AtomicInteger(0);
483	SplittableRandom r = new SplittableRandom();
484	long size = 456;
485	for (double least = 0.00011; least < 1.0e20; least *= 9) {
486	for (double bound = least * 1.0011; bound < 1.0e20; bound *= 17) {
487	final double lo = least, hi = bound;
488	r.doubles(size, lo, hi).parallel().forEach(
489	x -> {
490	if (x < lo \|\| x >= hi)
491	fails.getAndIncrement(); });
492	}
493	}
494	assertEquals(0, fails.get());
495	}
496
497	/**
498	* A parallel unsized stream of ints generates at least 100 values
499	*/
500	public void testUnsizedIntsCount() {
501	LongAdder counter = new LongAdder();
502	SplittableRandom r = new SplittableRandom();
503	long size = 100;
504	r.ints().limit(size).parallel().forEach(x -> counter.increment());
505	assertEquals(size, counter.sum());
506	}
507
508	/**
509	* A parallel unsized stream of longs generates at least 100 values
510	*/
511	public void testUnsizedLongsCount() {
512	LongAdder counter = new LongAdder();
513	SplittableRandom r = new SplittableRandom();
514	long size = 100;
515	r.longs().limit(size).parallel().forEach(x -> counter.increment());
516	assertEquals(size, counter.sum());
517	}
518
519	/**
520	* A parallel unsized stream of doubles generates at least 100 values
521	*/
522	public void testUnsizedDoublesCount() {
523	LongAdder counter = new LongAdder();
524	SplittableRandom r = new SplittableRandom();
525	long size = 100;
526	r.doubles().limit(size).parallel().forEach(x -> counter.increment());
527	assertEquals(size, counter.sum());
528	}
529
530	/**
531	* A sequential unsized stream of ints generates at least 100 values
532	*/
533	public void testUnsizedIntsCountSeq() {
534	LongAdder counter = new LongAdder();
535	SplittableRandom r = new SplittableRandom();
536	long size = 100;
537	r.ints().limit(size).forEach(x -> counter.increment());
538	assertEquals(size, counter.sum());
539	}
540
541	/**
542	* A sequential unsized stream of longs generates at least 100 values
543	*/
544	public void testUnsizedLongsCountSeq() {
545	LongAdder counter = new LongAdder();
546	SplittableRandom r = new SplittableRandom();
547	long size = 100;
548	r.longs().limit(size).forEach(x -> counter.increment());
549	assertEquals(size, counter.sum());
550	}
551
552	/**
553	* A sequential unsized stream of doubles generates at least 100 values
554	*/
555	public void testUnsizedDoublesCountSeq() {
556	LongAdder counter = new LongAdder();
557	SplittableRandom r = new SplittableRandom();
558	long size = 100;
559	r.doubles().limit(size).forEach(x -> counter.increment());
560	assertEquals(size, counter.sum());
561	}
562
563	}