Search:

As the state of your program changes, you should be able to change the components by removing them and adding others.

Do you mean you want to remove the currently displayed components in the window and replace them with a new set?

What are the "effects" you are looking for with only one window?

Do you want to have two windows?
If you create a class that extends JFrame and that class adds some components and calls setVisible you will have a window displayed.

If the second class extends...