Statistics.java

import com.google.common.math.Stats;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
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 java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@State(Scope.Thread)
public class Statistics {

    @Param({"10", "1000", "100000"})
    int size;

    int[] array;

    @Setup
    public void setUp() {
        this.array = ThreadLocalRandom.current().ints().limit(this.size).toArray();
    }

    @Benchmark
    public double sum() {
        double sum = 0;
        for (final int a : this.array) {
            sum += a;
        }
        return sum;
    }

    @Benchmark
    public double sumStats() {
        return Stats.of(this.array).sum();
    }
}