public static int getPassengerCount(SimpleTrain train) {
		if(train == null){
			LOG.error("Train is null");
			throw new IllegalArgumentException("Train is null");
		}
		int count = 0;
		for (AbstractCarriage ac : train) {
			if (ac instanceof AbstractPassengerCarriage) {
				count += ((AbstractPassengerCarriage) ac).getPassengerCurCount();
			}
		}
		return count;
	}