A good answer might be:

Not really.

Picture of the Relations

Perhaps a picture is needed. Clouds represent class definitions, and rectangles represent objects. The interface is a dotted rectangle (becuase it is neither a class nor an object.) The main() method is static, also represented with a dotted rectangle.

Look back at the example program as you study the diagram.

  • The class buttonDemo extends the class Frame.
  • The main() method is static, so is not part of any object.
    • Main contains two reference variables:
      • frm, which refers to a buttonDemo object, and
      • wquit, which refers to a WindowQuitter object
  • There is a single buttonDemo object, which will be the frame the users sees on the monitor screen.
  • There is a single Button object (which will appear inside of the frame.)
  • Events from the button are sent to the buttonDemo object.
    • The buttonDemo object was registered as a listener for Action Events.
    • The buttonDemo class implements ActionListener.
  • Events from the frame are sent to the WindowQuitter object.
    • The WindowQuitter object was registered as a listener for Window Events.
    • The WindowQuitter class extends WindowAdapter.
Don't be discouraged if this is less than perfectly clear! It usually takes some time to get all of these relationships straight. A bit more practice would not hurt, either.

QUESTION 13:

(Thought question: ) Do you have to use the "close button" of a frame to quit the program? Could an ordinary Button be used?

Click Here after you have answered the question