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
18 package org.apache.commons.rng.examples.jmh.core;
19
20 import org.apache.commons.rng.UniformRandomProvider;
21 import org.openjdk.jmh.annotations.Benchmark;
22 import org.openjdk.jmh.annotations.Scope;
23 import org.openjdk.jmh.annotations.State;
24
25 /**
26 * Executes benchmark to compare the speed of generation of random numbers from the
27 * various source providers for {@link UniformRandomProvider#nextInt()} and
28 * {@link UniformRandomProvider#nextInt(int)}.
29 */
30 public class NextIntGenerationPerformance extends AbstractBenchmark {
31 /** The value. Must NOT be final to prevent JVM optimisation! */
32 private int value;
33
34 /**
35 * The benchmark state (retrieve the various "RandomSource"s).
36 */
37 @State(Scope.Benchmark)
38 public static class Sources extends BaselineSources {
39 /** {@inheritDoc} */
40 @Override
41 protected UniformRandomProvider createBaseline() {
42 return BaselineUtils.getNextInt();
43 }
44 }
45
46 /**
47 * Baseline for a JMH method call with no return value.
48 */
49 @Benchmark
50 public void baselineVoid() {
51 // Do nothing, this is a baseline
52 }
53
54 /**
55 * Baseline for a JMH method call returning an {@code int}.
56 *
57 * @return the value
58 */
59 @Benchmark
60 public int baselineInt() {
61 return value;
62 }
63
64 /**
65 * Exercise the {@link UniformRandomProvider#nextInt()} method.
66 *
67 * @param sources Source of randomness.
68 * @return the int
69 */
70 @Benchmark
71 public int nextInt(Sources sources) {
72 return sources.getGenerator().nextInt();
73 }
74
75 /**
76 * Exercise the {@link UniformRandomProvider#nextInt(int)} method.
77 *
78 * @param sources Source of randomness.
79 * @return the int
80 */
81 @Benchmark
82 public int nextIntN(Sources sources) {
83 return sources.getGenerator().nextInt(BaselineGenerationPerformance.NEXT_INT_LIMIT);
84 }
85 }