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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.math4.legacy.genetics;
18  
19  import java.util.Iterator;
20  import java.util.concurrent.TimeUnit;
21  
22  import org.apache.commons.math4.core.jdkmath.JdkMath;
23  import org.junit.Assert;
24  import org.junit.Test;
25  
26  public class FixedElapsedTimeTest {
27  
28      @Test
29      public void testIsSatisfied() {
30          final Population pop = new Population() {
31              @Override
32              public void addChromosome(final Chromosome chromosome) {
33                  // unimportant
34              }
35              @Override
36              public Chromosome getFittestChromosome() {
37                  // unimportant
38                  return null;
39              }
40              @Override
41              public int getPopulationLimit() {
42                  // unimportant
43                  return 0;
44              }
45              @Override
46              public int getPopulationSize() {
47                  // unimportant
48                  return 0;
49              }
50              @Override
51              public Population nextGeneration() {
52                  // unimportant
53                  return null;
54              }
55              @Override
56              public Iterator<Chromosome> iterator() {
57                  // unimportant
58                  return null;
59              }
60          };
61  
62          final long start = System.nanoTime();
63          final long duration = 3;
64          final FixedElapsedTime tec = new FixedElapsedTime(duration, TimeUnit.SECONDS);
65  
66          while (!tec.isSatisfied(pop)) {
67              try {
68                  Thread.sleep(50);
69              } catch (InterruptedException e) {
70                  // ignore
71              }
72          }
73  
74          final long end = System.nanoTime();
75          final long elapsedTime = end - start;
76          final long diff = JdkMath.abs(elapsedTime - TimeUnit.SECONDS.toNanos(duration));
77  
78          Assert.assertTrue(diff < TimeUnit.MILLISECONDS.toNanos(100));
79      }
80  }