simple.java

The code to demonstrate simple GUI in Java

import javax.swing.JFrame;
public class Simple extends JFrame {
    public Simple() {
        setSize(300, 200);
        setTitle("Simple");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
   }
    public static void main(String[] args) {
        Simple simple = new Simple();
        simple.setVisible(true);
    }
}