Create a DO NOT ENTER Sign using java!

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import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;

import javax.swing.JFrame;
import javax.swing.JPanel;

/**
 * A panel maintaining a picture of a do not enter sign.
 */
 public class DoNotEnterSign extends JPanel {

    /**
     * Called by the runtime system whenever the panel needs painting.
     * TODO: This code has too many literals sprinkled about.
     */
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        Point center = new Point(getWidth() / 2, getHeight() / 2);
        int radius = Math.min(getWidth() / 2, getHeight() / 2) - 5;
        int innerRadius = (int)(radius * 0.9);

        g.setColor(Color.WHITE);
        g.fillOval(center.x - radius, center.y - radius,
                   radius * 2, radius * 2);
        g.setColor(Color.RED);
        g.fillOval(center.x - innerRadius, center.y - innerRadius,
                   innerRadius * 2, innerRadius * 2);
        g.setColor(Color.WHITE);
        int barWidth = (int)(innerRadius * 1.4);
        int barHeight = (int)(innerRadius * 0.35);
        g.fillRect(center.x - barWidth/2, center.y - barHeight/2,
                   barWidth, barHeight);
    }

    /**
     * A tester method that embeds the panel in a frame so you can "run"
     * it as an application.  Because we have nothing better to do, we
     * show off a bit of color manipulation.
     */
    public static void main(String[] args) {
        JFrame frame = new JFrame("A simple graphics program");
        frame.setSize(400, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new DoNotEnterSign();
        panel.setBackground(Color.GREEN.darker());
        frame.getContentPane().add(panel, BorderLayout.CENTER);
        frame.setVisible(true);
    }
}