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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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,
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 *
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package org.openjdk.jmh.benchmarks;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
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.State;
import org.openjdk.jmh.annotations.Warmup;

import java.util.concurrent.TimeUnit;

@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Thread)
@BenchmarkMode(Mode.AverageTime)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
public class NanoTimerBench {

    private long last;

    @Benchmark
    public long latency() {
        return System.nanoTime();
    }

    @Benchmark
    public long granularity() {
        long lst = last;
        long cur;
        do {
            cur = System.nanoTime();
        } while (cur == lst);
        last = cur;
        return cur;
    }
}
