jdk-24/test/micro/org/openjdk/bench/java/time/LeapYearBench.java
2023-11-08 15:18:53 +00:00

109 lines
3.4 KiB
Java

/*
* Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package org.openjdk.bench.java.time;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.infra.Blackhole;
import java.time.Duration;
import java.time.Instant;
import java.time.Year;
import java.time.ZonedDateTime;
import java.time.chrono.IsoChronology;
import java.time.temporal.ChronoUnit;
import java.util.GregorianCalendar;
import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.stream.IntStream;
/**
* Examine Year.leapYear-related operations
*/
@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
@Fork(3)
@State(Scope.Thread)
public class LeapYearBench {
private long[] years;
private GregorianCalendar calendar;
@Setup
public void createInstants() {
// Large enough number of years to guarantee that the distribution of
// leap years is reasonably realistic
years = new long[2048];
final Random random = new Random(0);
for (int i = 0; i < years.length; i++) {
years[i] = random.nextLong(2000) + 2000;
}
calendar = GregorianCalendar.from(ZonedDateTime.now());
}
@Benchmark
public void isLeapYear(Blackhole bh) {
for (long year : years) {
bh.consume(Year.isLeap(year));
}
}
@Benchmark
public void isLeapYearChrono(Blackhole bh) {
for (long year : years) {
bh.consume(IsoChronology.INSTANCE.isLeapYear(year));
}
}
@Benchmark
public void isLeapYearGregorian(Blackhole bh) {
for (long year : years) {
bh.consume(calendar.isLeapYear((int)year));
}
}
public static boolean isLeapNeriSchneider(long year) {
int d = year % 100 != 0 ? 4 : 16;
return (year & (d - 1)) == 0;
}
@Benchmark
public void isLeapYearNS(Blackhole bh) {
for (long year : years) {
bh.consume(isLeapNeriSchneider(year));
}
}
}