//  DateDistance.java  (c) 2005 Kari Laitinen

//  http://www.naturalprogramming.com

//  2005-07-25  File created.
//  2005-07-25  Last modification.

/*  This file contains the definition of class DateDistance,
    which is needed sometimes when class Date is used.
    To compile Date.java, you need to have this file in the
    same folder.

    A DateDistance object can store the chronological
    distance between two Date objects.

    Method get_distance_to() of class Date returns
    distance information to its caller inside a DateDistance
    object.
*/

class DateDistance
{
   public int years ;
   public int months ;
   public int days ;
}



/*  The DateDistance class could alternatively be introduced
    as a static inner class inside the Date class. (Inner classes
    are classes that are introduced inside other classes. They
    are not discussed in the book.) The class could be declared
    in the following way after the toString() method, and before
    the last closing brace } of the Date class:

   public static class Distance
   {
      public int years ;
      public int months ;
      public int days ;
   }

    After this modification the beginning of method get_distance_to()
    of class Date should be modified to look like the following

   public Date.Distance  get_distance_to( Date  another_date )
   {
      Date.Distance  distance_to_return  =  new Date.Distance() ;


    Then programs that use the get_distance_to() method should
    be modified so that Date.Distance would be written in place
    of DateDistance. For example, in Columbus.java should have
    the following statement:

      Date.Distance  distance_between  =

        date_of_discovery_of_america.get_distance_to( 
                                        date_of_first_moon_landing ) ;

******/