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.annotations.DataProvider;
25 import org.testng.annotations.Test;
26
27 import java.security.SecureRandom;
28 import java.util.ArrayList;
29 import java.util.List;
30
31 import java.util.Random;
32 import java.util.Set;
33 import java.util.concurrent.CompletableFuture;
34 import java.util.concurrent.ExecutionException;
35 import java.util.concurrent.ThreadLocalRandom;
36 import java.util.concurrent.TimeUnit;
37 import java.util.concurrent.TimeoutException;
38 import java.util.function.Supplier;
39 import java.util.stream.Stream;
40
41 import static java.util.stream.Collectors.toList;
42 import static java.util.stream.Collectors.toSet;
43 import static org.testng.Assert.*;
44
45 /**
46 * @test
47 * @run testng RandomStreamTest
48 * @summary test stream methods on Random
49 * @author Brian Goetz
50 * @key randomness
51 */
52 public class RandomStreamTest {
53
54 private static final int SIZE = 1000;
55
56 @DataProvider(name = "suppliers")
57 public Object[][] randomSuppliers() {
58 return new Object[][] {
59 {new Random(), SIZE},
60 {new SecureRandom(), SIZE}
61 };
62 }
63
64 @Test(dataProvider = "suppliers")
65 public void testRandomIntStream(final Random random, final int count) {
66 final List<Integer> destination = new ArrayList<>(count);
67 random.ints().limit(count).forEach(destination::add);
68 assertEquals(destination.size(), count);
69 }
70
71 @Test(dataProvider = "suppliers")
72 public void testRandomLongStream(final Random random, final int count) {
73 final List<Long> destination = new ArrayList<>(count);
74 random.longs().limit(count).forEach(destination::add);
75 assertEquals(destination.size(), count);
76 }
77
78 @Test(dataProvider = "suppliers")
79 public void testRandomDoubleStream(final Random random, final int count) {
80 final List<Double> destination = new ArrayList<>(count);
81 random.doubles().limit(count).forEach(destination::add);
82 random.doubles().limit(count).forEach(d -> assertTrue(d >= 0.0 && d < 1.0));
83 assertEquals(destination.size(), count);
84 }
85
86 @Test
87 public void testIntStream() {
88 final long seed = System.currentTimeMillis();
89 final Random r1 = new Random(seed);
90 final int[] a = new int[SIZE];
91 for (int i=0; i < SIZE; i++) {
92 a[i] = r1.nextInt();
93 }
94
95 final Random r2 = new Random(seed); // same seed
96 final int[] b = r2.ints().limit(SIZE).toArray();
97 assertEquals(a, b);
98 }
99
100 @Test
101 public void testLongStream() {
102 final long seed = System.currentTimeMillis();
103 final Random r1 = new Random(seed);
104 final long[] a = new long[SIZE];
105 for (int i=0; i < SIZE; i++) {
106 a[i] = r1.nextLong();
107 }
108
109 final Random r2 = new Random(seed); // same seed
110 final long[] b = r2.longs().limit(SIZE).toArray();
111 assertEquals(a, b);
112 }
113
114 @Test
115 public void testDoubleStream() {
116 final long seed = System.currentTimeMillis();
117 final Random r1 = new Random(seed);
118 final double[] a = new double[SIZE];
119 for (int i=0; i < SIZE; i++) {
120 a[i] = r1.nextDouble();
121 }
122
123 final Random r2 = new Random(seed); // same seed
124 final double[] b = r2.doubles().limit(SIZE).toArray();
125 assertEquals(a, b);
126 }
127
128 @Test
129 public void testThreadLocalIntStream() throws InterruptedException, ExecutionException, TimeoutException {
130 ThreadLocalRandom tlr = ThreadLocalRandom.current();
131 testRandomResultSupplierConcurrently(() -> tlr.ints().limit(SIZE).boxed().collect(toList()));
132 }
133
134 @Test
135 public void testThreadLocalLongStream() throws InterruptedException, ExecutionException, TimeoutException {
136 ThreadLocalRandom tlr = ThreadLocalRandom.current();
137 testRandomResultSupplierConcurrently(() -> tlr.longs().limit(SIZE).boxed().collect(toList()));
138 }
139
140 @Test
141 public void testThreadLocalDoubleStream() throws InterruptedException, ExecutionException, TimeoutException {
142 ThreadLocalRandom tlr = ThreadLocalRandom.current();
143 testRandomResultSupplierConcurrently(() -> tlr.doubles().limit(SIZE).boxed().collect(toList()));
144 }
145
146 <T> void testRandomResultSupplierConcurrently(Supplier<T> s) throws InterruptedException, ExecutionException, TimeoutException {
147 // Produce 10 completable future tasks
148 final int tasks = 10;
149 List<CompletableFuture<T>> cfs = Stream.generate(() -> CompletableFuture.supplyAsync(s)).
150 limit(tasks).collect(toList());
151
152 // Wait for all tasks to complete
153 // Timeout is beyond reasonable doubt that completion should
154 // have occurred unless there is an issue
155 CompletableFuture<Void> all = CompletableFuture.allOf(cfs.stream().toArray(CompletableFuture[]::new));
156 all.get(1, TimeUnit.MINUTES);
157
158 // Count the distinct results, which should equal the number of tasks
159 long rc = cfs.stream().map(CompletableFuture::join).distinct().count();
160 assertEquals(rc, tasks);
161 }
162 }