clip images with Java

/* MD Harrington  London  UK */



import com.sun.imageio.plugins.common.ImageUtil;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Ellipse2D;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
class Surface extends JPanel implements ActionListener {

    private int pos_x = 8;
    private int pos_y = 8;
    private final int RADIUS = 200;
    private final int DELAY = 10;
    private Timer timer;
    private Image image;
    private final double delta[] = { 3, 3 };

    public Surface() {
        setDoubleBuffered(true);
        this.setBackground(Color.black);
        loadImage();
        determineAndSetImageSize();
        initTimer();
    }

    private void loadImage() {
        try {
            image = javax.imageio.ImageIO.read(Surface.class.getClassLoader().getResourceAsStream("images/storm.jpg"));
        } catch (IOException ex) {
            Logger.getLogger(Surface.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    private void determineAndSetImageSize() {
        int h = image.getHeight(this);
        System.out.println("Height = " +h);
        int w = image.getWidth(this);
        setPreferredSize(new Dimension(w, h));
    }

    private void initTimer() {
        timer = new Timer(DELAY, this);
        timer.start();
    }

    private void doDrawing(Graphics g) {
        Graphics2D g2d = (Graphics2D) g.create();
        g2d.clip(new Ellipse2D.Double(pos_x, pos_y, RADIUS, RADIUS));
        g2d.drawImage(image, 0, 0, null);
        g2d.dispose();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        doDrawing(g);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        moveCircle();
        repaint();
    }

    private void moveCircle() {
        int w = getWidth();
        int h = getHeight();
        if (pos_x < 0) {
            delta[0] = Math.random() % 4 + 2;
        } else if (pos_x > w - RADIUS) {
            delta[0] = -(Math.random() % 4 + 2);
        }
        if (pos_y < 0 ) {
            delta[1] = Math.random() % 4 + 2;

        } else if (pos_y > h - RADIUS) {
            delta[1] = -(Math.random() % 4 + 2);
        }

        pos_x += delta[0];
        pos_y += delta[1];
    }

}
public class ClippingEx extends JFrame
 {
    public ClippingEx() {
        initUI();
    }

    private void initUI() {
        setTitle("Clipping");
        setBackground(Color.black);
        add(new Surface());
        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                ClippingEx cl = new ClippingEx();
                cl.setVisible(true);
            }
        });
    }
}