Programmation java

import javax.swing.JFrame;
import javax.swing.JLabel;
 
public class HelloWorld 
{
    public static void main(String[] args)
    {
       JFrame frame = new JFrame("Hello World!");
       frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
       frame.getContentPane().add((new JLabel("Hello, World!")));
       frame.pack();
       frame.setLocationRelativeTo(null);
       frame.setVisible(true);
    }
}