code: public FlightInfoExtendedBuilder setArrivalAirport(String airportCode,
  			String city, String gate, String terminal) {
  		Airport arrivalAirport = new Airport(airportCode, city, gate, terminal);
  		this.flightInfo.setArrivalAirport(arrivalAirport);
  		return this;
  	}
docs: Sets the arrival {@link Airport} for the current
  {@link FlightInfoExtended} object. This field is mandatory for this
  object and can't be null.
  
  @param airportCode
  the airport code. It can't be empty.
  @param city
  the city name. The city will be displayed over the airport
  code in the template. It can't be empty.
  @param gate
  the airport gate. This field is optional.
  @param terminal
  the airport terminal. This field is optional.
  @return this builder.