package jdk.test;

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 java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

@State(Scope.Thread)
@Fork(1)
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Warmup(iterations = 7)
@Measurement(iterations = 10)
public class UnmodifiableMapOfBench {

    Integer i1, i2, i3, i4, i5, i6, i7, i8, i9, i10;

    @SuppressWarnings("deprecation")
    @Setup
    public void setup() {
        Iterator<Integer> ii =
            ThreadLocalRandom.current()
                             .ints(20)
                             .mapToObj(Integer::new)
                             .collect(Collectors.toCollection(LinkedHashSet::new))
                             .iterator();
        i1 = ii.next();
        i2 = ii.next();
        i3 = ii.next();
        i4 = ii.next();
        i5 = ii.next();
        i6 = ii.next();
        i7 = ii.next();
        i8 = ii.next();
        i9 = ii.next();
        i10 = ii.next();
    }

    @Benchmark
    public Map<Integer, Integer> of_2() {
        return Map.of(i1, i1, i2, i2);
    }

    @Benchmark
    public Map<Integer, Integer> of_3() {
        return Map.of(i1, i1, i2, i2, i3, i3);
    }

    @Benchmark
    public Map<Integer, Integer> of_4() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4);
    }

    @Benchmark
    public Map<Integer, Integer> of_5() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5);
    }

    @Benchmark
    public Map<Integer, Integer> of_6() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5, i6, i6);
    }

    @Benchmark
    public Map<Integer, Integer> of_7() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5, i6, i6, i7, i7);
    }

    @Benchmark
    public Map<Integer, Integer> of_8() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5, i6, i6, i7, i7, i8, i8);
    }

    @Benchmark
    public Map<Integer, Integer> of_9() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5, i6, i6, i7, i7, i8, i8, i9, i9);
    }

    @Benchmark
    public Map<Integer, Integer> of10() {
        return Map.of(i1, i1, i2, i2, i3, i3, i4, i4, i5, i5, i6, i6, i7, i7, i8, i8, i9, i9, i10, i10);
    }
}