title: Classes in Java
body: <p>I am new in Java so it will be a newbie question, here it is:</p>
  
  <p>I have a class Airplane. But I must have different Airplanes (like PassengerPlane or CargoPlane)
  Then I have to use this planes in another class (for example Airport) as Airplane.</p>
  
  <p>I mean, how can I have different attributes (cargoPlane has maximum capacity, passengerPlane has maximum passengers for example) in the same class Airplane?</p>
  
  <p>Thanks in advance.</p>