My animation flickers.

[Somelauw]

I'm trying to draw an animation but for some reason, it flickers.

Here is my code:

package pong;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.RepaintManager;
import javax.swing.Timer;

public class Field extends JFrame{
    Timer timer;
    Ball ball = new Ball(200, 200);

    public Field() {
        setTitle("Pong");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(400, 400);
        setVisible(true);
        getContentPane().setBackground(Color.WHITE);

        new Timer(100, new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                ball.update();
                repaint();
            }
        }).start();
    }

    @Override
    public void paint(Graphics g) {
        super.paint(g);
        ball.draw(g);
    }

}

[curmudgeon]

Don't draw directly on the JFrame for by doing so you lose Swing's automatic double buffering (and can also cause other problems). Instead draw in a paintComponent override (not paint) of a JPanel and place the JPanel in the JFrame's content pane.