Swing/MouseInfo のバックアップ(No.6)

public static final Dimension panelDim = new Dimension(320, 240);
private final Racket racket = new Racket(panelDim);
public MainPanel() {
  super(new BorderLayout());
  setPreferredSize(panelDim);
  new javax.swing.Timer(10, this).start();
}
@Override public void paintComponent(Graphics g) {
  super.paintComponent(g);
  racket.draw(g);
}
@Override public void actionPerformed(ActionEvent e) {
  PointerInfo pi = MouseInfo.getPointerInfo();
  Point pt = pi.getLocation();
  SwingUtilities.convertPointFromScreen(pt, this);
  racket.move(pt.x);
  repaint();
}