MyForkJoinPool.java

@Component
public class MyForkJoinPool {
    private static final Logger LOGGER = LoggerFactory.getLogger(MyForkJoinPool.class);

    private ForkJoinPool forkJoinPool;
    private ForkJoinPool hardForkJoinPool;

    @PostConstruct
    public void init() {
        this.forkJoinPool = new ForkJoinPool(2);
        this.hardForkJoinPool = new ForkJoinPool(4);
    }

    public void submit(Runnable task) {
        if (this.forkJoinPool != null) {
            this.forkJoinPool.execute(task);
        } else {
            LOGGER.error("Fork Join Pool is null");
        }
    }

    public void submitHard(List<Runnable> tasks) {
        if (this.hardForkJoinPool != null) {

            List<ForkJoinTask> fjTasks = new ArrayList<>();
            tasks.forEach(t -> fjTasks.add(this.hardForkJoinPool.submit(t)));

            LOGGER.info("Tasks submitted: {}", tasks.size());

            fjTasks.forEach(ForkJoinTask::join);
            LOGGER.info("Tasks finished: {}", fjTasks.size());

        } else {
            LOGGER.error("Fork Join Pool is null");
        }
    }
}