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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package org.openjdk.bench.java.time;

import java.time.Duration;
import java.time.Instant;
import java.time.temporal.ChronoUnit;

import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.stream.IntStream;

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.Param;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;

/**
 * Examine Instant.plusSeconds operations
 */
@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
@Fork(3)
@State(Scope.Thread)
public class InstantBench {

    private Instant[] INSTANTS;
    private int[] SECONDS;

    private long[] RESULT;

    @Setup
    public void createInstants() {
        // Various instants during the same day
        final Instant loInstant = Instant.EPOCH.plus(Duration.ofDays(365*50)); // 2020-01-01
        final Instant hiInstant = loInstant.plus(Duration.ofDays(1));
        final long maxOffsetNanos = Duration.between(loInstant, hiInstant).toNanos();
        final Random random = new Random(0);
        INSTANTS = IntStream
                .range(0, 1_000)
                .mapToObj(ignored -> {
                    final long offsetNanos = (long) Math.floor(random.nextDouble() * maxOffsetNanos);
                    return loInstant.plus(offsetNanos, ChronoUnit.NANOS);
                })
                .toArray(Instant[]::new);
        SECONDS = IntStream
                .range(0, INSTANTS.length)
                .map(ignored -> random.nextInt(1000))
                .toArray();
        RESULT = new long[INSTANTS.length];
    }

    @Benchmark
    public long[] plusSecondsDropNanos() {
        for (int i = 0; i < INSTANTS.length; i++) {
            RESULT[i] = INSTANTS[i].plusSeconds(SECONDS[i]).getEpochSecond();
        }
        return RESULT;
    }
}