Kassa a = new Kassa(settings);
a.open(); // в этот момент больше никто к кассе не может подключиться, open может выполняться несколько секунд
Result r = a.processTask("some json"); // может выполняться несколько секунд
a.close();

Kassa a = new Kassa(settings1);
Kassa b = new Kassa(settings2);
a.open();
b.open();

Kassa a = new Kassa(settings);
Kassa b = new Kassa(settings);

Kassa a = new Kassa(settings);
Kassa b = new Kassa(settings);

Kassa a = new Kassa(settings1);

	class Barber extends Thread {
		BlockingQueue<Integer> queue = null;
		private String name;

		public Barber(BlockingQueue<Integer> queue, String name) {
			this.name = name;
			this.queue = queue;
		}

		public void run() {
			while (true) { // runs in an infinite loop

				try {
					Integer i = this.queue.poll(OFFICE_CLOSE,
							TimeUnit.MILLISECONDS);
					if (i == null)
						break; // barber slept for long time (OFFICE_CLOSE) no
								// more clients in the queue - close office
					this.cutHair(i); // cutting...

				} catch (InterruptedException e) {
				}
			}
		}

		public void cutHair(Integer i) {
			System.out.println("The barber " + this.name
					+ " is cutting hair for customer #" + i);
			try {
				sleep(BARBER_TIME);
			} catch (InterruptedException ex) {
			}
		}
	}

{
  "inn": "1111111111", // по инн однозначно определяется касса
  "request": {
    "type": "sell",
    "taxationType": "osn",
    "ignoreNonFiscalPrintErrors": false,
    "electronically": false,
    "operator": {
      "name": "Иванов",
      "vatin": "123654789507"
    },
    "clientInfo": {
      "emailOrPhone": "+7912345678"
    },
    "items": [
      {
        "type": "position",
        "name": "Бананы",
        "price": 1.0,
        "quantity": 1.0,
        "amount": 1.0,
        "paymentObject": "commodity",
        "tax": {
          "type": "vat18"
        }
      },
      {
        "type": "position",
        "name": "Апельсины",
        "price": 1.0,
        "quantity": 1.0,
        "amount": 1.0,
        "paymentObject": "commodity",
        "tax": {
          "type": "vat18"
        }
      }
    ],
    "payments": [
      {
        "type": "cash",
        "sum": 2.00
      }
    ]
  }
}