test_stream_parallel_forkjoin_threadpool

test_stream_parallel_forkjoin_threadpool.java

@Test
public void test() throws InterruptedException, ExecutionException {
    ForkJoinPool customThreadPool = new ForkJoinPool(8);
    ThreadFactory threadFactory = new ThreadFactoryBuilder().setNameFormat("pool-%d").build();

    ThreadPoolExecutor executor = new ThreadPoolExecutor(5, Integer.MAX_VALUE,
        1, TimeUnit.MINUTES,
        new LinkedBlockingQueue<>(5),
        threadFactory,
        new ThreadPoolExecutor.AbortPolicy());

    long firstNum = 1;
    long lastNum = 30;
    Stream<Long> stream = LongStream.rangeClosed(firstNum, lastNum).boxed();
    Stream<Long> stream2 = LongStream.rangeClosed(firstNum, lastNum).boxed();
    Stream<Long> longStream = stream2.parallel();

    executor.submit(() -> {
        longStream.forEach(l -> {
            System.out.println(Thread.currentThread().getName() + ":" + l + " " + longStream.isParallel());
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException ignored) {}
        });
    }).get();

    long actualTotal = customThreadPool.submit(() -> {
        System.out.println(Thread.currentThread().getName() + ":" + stream.isParallel());
        return stream.reduce(0L, Long::sum);
    }).get();

    assertEquals((lastNum + firstNum) * lastNum / 2, actualTotal);
}

ForkJoinPool.commonPool-worker-3:5 true
ForkJoinPool.commonPool-worker-2:28 true
ForkJoinPool.commonPool-worker-4:2 true
ForkJoinPool.commonPool-worker-1:10 true
ForkJoinPool.commonPool-worker-6:7 true
pool-0:20 true
ForkJoinPool.commonPool-worker-5:14 true
ForkJoinPool.commonPool-worker-7:9 true
ForkJoinPool.commonPool-worker-2:27 true
ForkJoinPool.commonPool-worker-7:8 true
ForkJoinPool.commonPool-worker-1:11 true
ForkJoinPool.commonPool-worker-3:4 true
ForkJoinPool.commonPool-worker-4:3 true
ForkJoinPool.commonPool-worker-5:15 true
ForkJoinPool.commonPool-worker-6:6 true
pool-0:19 true
ForkJoinPool.commonPool-worker-2:30 true
ForkJoinPool.commonPool-worker-5:29 true
ForkJoinPool.commonPool-worker-1:1 true
ForkJoinPool.commonPool-worker-4:25 true
ForkJoinPool.commonPool-worker-3:13 true
pool-0:22 true
ForkJoinPool.commonPool-worker-6:12 true
ForkJoinPool.commonPool-worker-7:17 true
ForkJoinPool.commonPool-worker-2:21 true
ForkJoinPool.commonPool-worker-4:26 true
ForkJoinPool.commonPool-worker-7:18 true
pool-0:16 true
ForkJoinPool.commonPool-worker-6:23 true
ForkJoinPool.commonPool-worker-3:24 true
ForkJoinPool-1-worker-1:false