ParallelStream.java

import java.util.ArrayList;
import java.util.concurrent.locks.LockSupport;
import java.util.stream.StreamSupport;

public class ParallelStream {

    public static int[] process(Iterable<Integer> iterable) {
        return StreamSupport.stream(iterable.spliterator(), true)
                .mapToInt(i -> {
                    LockSupport.parkNanos(1_000_000);
                    return i;
                })
                .toArray();
    }

    public static void main(String[] args) {
        ArrayList<Integer> list = new ArrayList<>();
        for (int i = 0; i < 1000; i++) {
            list.add(i);
        }

        while (true) {
            long startTime = System.nanoTime();
            process(list::iterator);
//            process(list);
            long endTime = System.nanoTime();
            System.out.println((endTime - startTime) / 1e6 + " ms");
        }
    }
}