java game development course free

1package com.edu4java.minitennis1;
2import javax.swing.JFrame;
3
4public class Game {
5	public static void main(String[] args) {
6		JFrame frame = new JFrame("Mini Tennis");
7		frame.setSize(300, 300);
8		frame.setVisible(true);
9		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
10	}
11}