encapsulation

  • setting the access level in the class methods and attributes
    • public
    • protected
    • private

getter and setter functions

  • helps access and change private attributes

  • getter function only retrieves the current value

    • it cannot change the value

encapsulation boundaries

  • private properties do not extend to child classes, or the public object
  • protected properties extend to child classes, but not the public object
  • when overriding with functions in the child classes,
    • the access level can be same or weaker
    • not stronger
  • once the object is created,
    • only public attributes and methods can be accessed