>>157の続きです
public Sample() {
setTitle("Test");
setBounds(10, 10, 300, 250);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

p = new TestPanel();
getContentPane().add(p, BorderLayout.CENTER);
}

class TestPanel extends JPanel{
public TestPanel() {
setPreferredSize(new Dimension(200, 150));
}
public void paintComponent(Graphics g){
super.paintComponent(g);
g.drawLine(x, y, 200-x, 150-y);
}
}
}