class BigDate implements java.lang.Comparable
   {
   int ordinal;
   ... other fields ...

   /**
   * Defines Natural Order for the BigDate class.
   * Determines if this date comes after some other date.
   * Conceptually returns (this - anotherBigDate).
   * compareTo() == 0 is faster than equals().
   * @param anotherBigDate date to compare against
   * @return a positive number if this date > (after) anotherBigDate.

   * zero if this date = anotherBigDate.

   * a negative number if this date < (before) anotherBigDate.
   */
   public final int compareTo( Object anotherBigDate )
      {
      return this.ordinal - ( (BigDate)anotherBigDate).ordinal;
      }
   } // end class BigDate