//  EventsGregorianCalendar.cs (c) 2005 Kari Laitinen

//  http://www.naturalprogramming.com

//  2005-06-14  File created.
//  2005-06-14  Last modification.

//  A solution to exercise 15-9.

//  A different kind of solution is provided at the end of this file.


import java.util.* ;

//  As class GregorianCalendar already implements the Comparable
//  interface, the Event class does not need to implement it.
//  The compareTo() of class GregorianCalendar can compare
//  Event objects as well.

class  Event  extends GregorianCalendar
{
   protected String event_description ;

   public Event( int  day_of_event,
                 int  month_of_event,
                 int  year_of_event,
                 String given_event_description )
   {
      super( year_of_event, month_of_event, day_of_event ) ;

      event_description  =  given_event_description ;
   }


   public String toString()
   {
      return  String.format( "%tF   %s", this, event_description ) ;
   }
}

   /*  The following is a longer version of a suitable 
       toString() method for the above Event class.

   public String toString()
   {
      Calendar  date_of_event  =  new GregorianCalendar(
                                          get( Calendar.YEAR ),
                                          get( Calendar.MONTH ),
                                          get( Calendar.DAY_OF_MONTH ) ) ;

      return  String.format( "%tF   %s", date_of_event, event_description ) ;
   }
   ***/


class  EventsGregorianCalendar
{
   public static void main( String[] not_in_use )
   {
      Event  birth_of_lennon   =  new  Event(
                 9, 10, 1940, "John Lennon was born.") ;
      Event  birth_of_einstein =  new  Event(
                14,  3, 1879, "Albert Einstein was born." ) ;

      ArrayList<Event>  list_of_events  =  new  ArrayList<Event>() ;

      list_of_events.add( birth_of_lennon ) ;
      list_of_events.add( birth_of_einstein ) ;
      list_of_events.add( new
          Event( 8, 12, 1980, "John Lennon was shot in New York." ) ) ;

      System.out.print( "\nEvents of list_of_events: \n" ) ;

      int event_index  =  0 ;

      while ( event_index  <  list_of_events.size() )
      {
         System.out.print( "\n   "  +  list_of_events.get( event_index ) ) ;
         event_index  ++  ;
      }


      ArrayList<Event>  another_event_list  =  new  ArrayList<Event>() ;

      another_event_list.add( 0,
         new Event( 1, 6, 1926, "Marilyn Monroe was born." ) ) ;
      another_event_list.add( 0,
         new Event( 5, 8, 1962, "Marilyn Monroe died." ) ) ;
      another_event_list.add(
         new Event(15, 8, 1769, "Napoleon Bonaparte was born." ) ) ;
      another_event_list.add(
         new Event(25,10, 1881, "Pablo Picasso was born." ) ) ;


      System.out.print( "\n\nEvents of another_event_list: \n" ) ;

      for ( event_index  =  0 ;
            event_index  <  another_event_list.size() ;
            event_index  ++ )
      {
         System.out.print( "\n   "  +  another_event_list.get( event_index ) );
      }

      Collections.sort( list_of_events ) ;
      Collections.sort( another_event_list ) ;

      list_of_events.addAll( 0, another_event_list ) ;

      System.out.print( "\n\nEvents of list_of_events: \n" ) ;

      for ( Event event_on_list : list_of_events )
      {
         System.out.print( "\n   "  +  event_on_list ) ;
      }
   }
}

/****

//  The following version of class Event would also work.
//  This Event class has a Calendar object as a data field.

class  Event implements Comparable<Event>
{
   protected Calendar date_of_event ;

   protected String event_description ;

   public Event( int  day_of_event,
                 int  month_of_event,
                 int  year_of_event,
                 String given_event_description )
   {

      date_of_event  =  new  GregorianCalendar( 
                               year_of_event, month_of_event, day_of_event ) ;

      event_description  =  given_event_description ;
   }


   public String toString()
   {
      return  String.format( "%tF   %s", date_of_event, event_description ) ;
   }

   public int compareTo( Event event_to_compare_to )
   {
      return  date_of_event.compareTo( event_to_compare_to.date_of_event ) ;
   }
}

***/