bench

Main.java

package com.github.larhat;

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.Level;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;
import org.openjdk.jmh.runner.options.TimeValue;

import java.util.HashSet;
import java.util.Random;
import java.util.Set;
import java.util.concurrent.TimeUnit;


public class Main {
    private final static int FIRST_BOOK_ID = 3512512;
    private final static int LAST_BOOK_ID = 3512512 * 4;
    private final static int TOTAL_NUMBER = 141553;
    private final static int TOTAL_EVENTS = 429392;

    @State(Scope.Benchmark)
    public static class BenchmarkState {
        private Set<Long> theHashSet;
        private BookIds theBookIds;
        private long[] theSelected;
        private int thePos = 0;
        private long theCur;

        @Setup(Level.Trial)
        public void setup() {
            int myPerExpiry = TOTAL_NUMBER / 32;
            theHashSet = new HashSet<>(myPerExpiry);
            Random myRandom = new Random();
            for (int myI = 0; myI < myPerExpiry; myI++) {
                theHashSet.add((long)FIRST_BOOK_ID + myRandom.nextInt(LAST_BOOK_ID));
            }
            theSelected = new long[TOTAL_EVENTS];
            for (int myI = 0; myI < theSelected.length; myI++) {
                theSelected[myI] = (long)FIRST_BOOK_ID + myRandom.nextInt(LAST_BOOK_ID);
            }
            theBookIds = BookIds.create(theHashSet, Long::longValue);
        }

        @Setup(Level.Invocation)
        public void setupCounter() {
            thePos = (thePos + 1) % theSelected.length;
            theCur = theSelected[thePos];
        }
    }

    @Benchmark
    public boolean hashSet(BenchmarkState aBenchmarkState) {
        return aBenchmarkState.theHashSet.contains(aBenchmarkState.theCur);
    }

    @Benchmark
    public boolean bookIds(BenchmarkState aBenchmarkState) {
        return aBenchmarkState.theBookIds.contains(aBenchmarkState.theCur);
    }

    public static void main(String[] args) throws RunnerException {
        Options opt = new OptionsBuilder()
                .include(Main.class.getSimpleName())
                .mode(Mode.AverageTime)
                .timeUnit(TimeUnit.NANOSECONDS)
                .warmupIterations(10)
                .measurementIterations(30)
                .measurementTime(TimeValue.seconds(5))
                .forks(1)
                .build();

        new Runner(opt).run();
    }
}