  import java.awt.Rectangle; 
 
  /** 
     Objects of this class measure rectangles by area. 
 */ 
  public class RectangleMeasurer implements Measurer 
  { 
     public double measure(Object anObject) 
     { 
       Rectangle aRectangle = (Rectangle) anObject; 
       double area = aRectangle.getWidth() * aRectangle.getHeight(); 
       return area; 
    } 
 } 
