@Override
    public StatisticResult call() {
        ExecutorService executor = Executors.newFixedThreadPool(4);

        Drop drop = new Drop();
        Random random = new Random();
        StatisticWorker statictic = new StatisticWorker(drop);
        Producer producer = new Producer(drop);

        executor.submit(producer);
        Future<StatisticResult> result = executor.submit(statictic);

        PrintWorker printWorker = new PrintWorker(statictic.getStatistic());
        executor.submit(printWorker);

        for (int i = 0; i < 500; i++) {
            executor.submit(new Consumer(drop));
            sleep(random);
        }

        printWorker.stop();
        producer.stop();
        statictic.stop();
        executor.shutdown();

        return getResult(result);
    }