android13/external/guava/guava-tests/benchmark/com/google/common/base/StopwatchBenchmark.java

51 lines
1.5 KiB
Java

/*
* Copyright (C) 2008 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.base;
import com.google.caliper.Benchmark;
import java.util.concurrent.TimeUnit;
/**
* Simple benchmark: create, start, read. This does not currently report the most useful result
* because it's ambiguous to what extent the stopwatch benchmark is being affected by GC.
*
* @author Kevin Bourrillion
*/
public class StopwatchBenchmark {
@Benchmark
long stopwatch(int reps) {
long total = 0;
for (int i = 0; i < reps; i++) {
Stopwatch s = Stopwatch.createStarted();
// here is where you would do something
total += s.elapsed(TimeUnit.NANOSECONDS);
}
return total;
}
@Benchmark
long manual(int reps) {
long total = 0;
for (int i = 0; i < reps; i++) {
long start = System.nanoTime();
// here is where you would do something
total += (System.nanoTime() - start);
}
return total;
}
}