Unable to run Java GUI programs with Ubuntu

Question

I am learning GUI in Java, and for that I have created a demo program:

import java.awt.*;

public class FrameDemo extends Frame {

    public FrameDemo(){
           


        

Answer 1

Use JFrame instead of Frame. And do not extend from JFrame. Just write a class that has a JFrame property named gui, which configures this JFrame with the available methods, because it is better style doing it like this. Extending here is wrong the use of OOP.