import java.applet.*;
import java.awt.*;
import javax.swing.*;

public class Exemple extends JApplet {

    public void init() {
        monApplication();
    }

    private void monApplication() {
        this.setPreferredSize(new Dimension(200,200));
        this.getContentPane().add(new JLabel("un label"));
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame();
        Exemple exemple= new Exemple();

        exemple.init();
        frame.getContentPane().add(exemple);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }
}