/** A class to represent our Solar System's planets
     *
     * @author - java.sun.com - Java Tutorial Example
     */
    public enum Planet 
   {
      MERCURY (3.303e+23, 2.4397e6),
      VENUS   (4.869e+24, 6.0518e6),
      EARTH   (5.976e+24, 6.37814e6),
      MARS    (6.421e+23, 3.3972e6),
      JUPITER (1.9e+27,   7.1492e7),
      SATURN  (5.688e+26, 6.0268e7),
      URANUS  (8.686e+25, 2.5559e7),
      NEPTUNE (1.024e+26, 2.4746e7); 
      // pluto's gone! How sad?
   
      private final double mass;   // in kilograms
      private final double radius; // in meters
       
       Planet(double mass, double radius) 
      {
         this.mass = mass;
         this.radius = radius;
      }
       private double mass()   
      { 
         return mass; 
      }
       private double radius() 
      { 
         return radius; 
      }
   
    // universal gravitational constant  (m3 kg-1 s-2)
      public static final double G = 6.67300E-11;
   
       double surfaceGravity() 
      {
         return G * mass / (radius * radius);
      }
       double surfaceWeight(double otherMass) 
      {
         return otherMass * surfaceGravity();
      }
       
       public static void main(String[] args) 
      {
         double earthWeight = Double.parseDouble(args[0]);
         double mass = earthWeight/EARTH.surfaceGravity();
         for (Planet p : Planet.values())
            System.out.printf("Your weight on %s is %f%n",
                             p, p.surfaceWeight(mass));
      }
   }