workQueue = new ArrayBlockingQueue<Runnable>(queueCapacity, true);
    }

    @Override
    public void enqueue(Runnable task) {
        addToQueue(task);
    }

    private void addToQueue(Runnable task) {
        if (closed) {
            throw new IllegalStateException("The worker has already been closed. Cannot add more work to queue.");
        }
        try {