// concurrent/CountingStream.java

// (c)2017 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// {VisuallyInspectOutput}

import java.util.*;

import java.util.concurrent.*;

import java.util.stream.*;

public class CountingStream {

public static void main(String[] args) {

System.out.println(

IntStream.range(0, 10)

.parallel()

.mapToObj(CountingTask::new)

.map(ct -> ct.call())

.reduce(0, Integer::sum));

}

}

/* Output:

1 ForkJoinPool.commonPool-worker-3 100

8 ForkJoinPool.commonPool-worker-2 100

0 ForkJoinPool.commonPool-worker-6 100

2 ForkJoinPool.commonPool-worker-1 100

4 ForkJoinPool.commonPool-worker-5 100

9 ForkJoinPool.commonPool-worker-7 100

6 main 100

7 ForkJoinPool.commonPool-worker-4 100

5 ForkJoinPool.commonPool-worker-2 100

3 ForkJoinPool.commonPool-worker-3 100

1000

*/