import javax.swing.JComponent;

 import java.util.*;

 import java.awt.*;

 import java.awt.geom.*;

 @SuppressWarnings("serial")

 public class SketcherView extends JComponent implements Observer {

   public SketcherView(Sketcher theApp) {

     this.theApp = theApp;

   }

   // Method called by Observable object when it changes

   public void update(Observable o, Object rectangle) {

     // Code to respond to changes in the model...

   }

   // Method to draw on the view

   @Override

   public void paint(Graphics g) {

     // Temporary code...

     Graphics2D g2D = (Graphics2D)g;                                    // Get a Java 2D device context

     Point2D.Double position = new Point2D.Double(50,10);               // Initial position

     double width = 150;                                                // Width of ellipse

     double height = 100;                                               // Height of ellipse

     double start = 30;                                                 // Start angle for arc

     double extent = 120;                                               // Extent of arc

     double diameter = 40;                                              // Diameter of circle

     // Define open arc as an upper segment of an ellipse

     Arc2D.Double top = new Arc2D.Double(position.x, position.y,

                                      width, height,

                                      start, extent,

                                      Arc2D.OPEN);

     // Define open arc as lower segment of ellipse shifted up relative to 1st

     Arc2D.Double bottom = new Arc2D.Double(

                                      position.x, position.y - height + diameter,

                                      width, height,

                                      start + 180, extent,

                                      Arc2D.OPEN);

     // Create a circle centered between the two arcs

     Ellipse2D.Double circle1 = new Ellipse2D.Double(

                                      position.x + width/2 - diameter/2,position.y,

                                      diameter, diameter);

     // Create a second circle concentric with the first and half the diameter

     Ellipse2D.Double circle2 = new Ellipse2D.Double(

                    position.x + width/2 - diameter/4, position.y + diameter/4,

                    diameter/2, diameter/2);

     // Draw all the shapes

     g2D.setPaint(Color.BLACK);                                         // Draw in black

     g2D.draw(top);

     g2D.draw(bottom);

     g2D.setPaint(Color.BLUE);                                          // Draw in blue

     g2D.draw(circle1);

     g2D.draw(circle2);

     g2D.drawString("Arcs and ellipses", 80, 100);                      // Draw some text

   }

   private Sketcher theApp;                                             // The application object

 }