Wert außerhalb ChangeListener

[GUIBeginner]

Hier ist mein jetziger Code!
Vielen Dank ! :-)

  
public class GUI extends JFrame {  
  
	public JPanel contentPane;  
	private Linien grafik;  
	/**  
	 * Launch the application.  
	 */  
	public static void main(String[] args) {  
		EventQueue.invokeLater(new Runnable() {  
			public void run() {  
				try {  
					GUI frame = new GUI();  
					frame.setVisible(true);  
				} catch (Exception e) {  
					e.printStackTrace();  
				}  
			}  
		});  
	}  
  
	/**  
	 * Create the frame.  
	 */  
	public GUI() {  
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  
		setBounds(100, 100, 450, 300);  
		contentPane = new JPanel();  
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));  
		setContentPane(contentPane);  
		contentPane.setLayout(null);  
		  
		final JSlider slider = new JSlider();  
		slider.addChangeListener(new ChangeListener() {  
			public void stateChanged(ChangeEvent arg0) {  
				grafik.d=((JSlider)arg0.getSource()).getValue();  
				System.out.println(grafik.d);  
				grafik.repaint();  
					  
			}  
		});  
		  
		  
		grafik = new Linien();  
		JPanel panel = new Linien();  
		panel.setBounds(77, 34, 137, 140);  
		contentPane.add(panel);  
		panel.setBackground(Color.ORANGE);  
  
		slider.setMajorTickSpacing(100);  
		slider.setValue(10);  
		slider.setPaintLabels(true);  
		slider.setBounds(125, 196, 200, 37);  
		contentPane.add(slider);  
		  
		}  
}  
  

und hier die Linien.java

  
public class Linien extends JPanel  
{  
	public int d;  
	  
	public Linien()  
	{  
		System.out.println("Lininen-d-Wert: "+d);  
	  
	}  
	 public void paintComponent(Graphics g){  
		super.paintComponent(g);  
		g.fillOval(10,10,d ,d);  
                repaint();  
	}  
}