1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.myfaces.util;
20
21 import org.junit.Test;
22 import org.testng.Assert;
23
24 import java.util.HashSet;
25 import java.util.Set;
26
27 public class XorShiftRandomTest
28 {
29
30 @Test
31 public void testXorShiftRandom()
32 {
33 XorShiftRandom random = new XorShiftRandom(System.nanoTime());
34 Set<Long> randomVals = new HashSet<Long>(10);
35
36 int randomCount = 100;
37
38 for (int i = 0; i < randomCount; i ++)
39 {
40 randomVals.add(random.random());
41 }
42
43 // if the random generator is good then we had no collisions.
44 Assert.assertEquals(randomVals.size(), 100);
45 }
46
47
48 @Test
49 public void testThreadsafeXorShiftRandom()
50 {
51 XorShiftRandom random = new ThreadsafeXorShiftRandom();
52 Set<Long> randomVals = new HashSet<Long>(10);
53
54 int randomCount = 100;
55
56 for (int i = 0; i < randomCount; i ++)
57 {
58 randomVals.add(random.random());
59 }
60
61 // if the random generator is good then we had no collisions.
62 Assert.assertEquals(randomVals.size(), 100);
63 }
64 }