public Vehicle(String vehID, int arrivalTime) throws VehicleException {

		if (arrivalTime <= 0) {
			throw new VehicleException("Arrival time must be 1 or greater.");
		}

		this.vehID = vehID;
		this.arrivalTime = arrivalTime;
		vehicleState = "arriving";
		// Vehicle arrives and enters the queue.
		enterQueuedState();
	}