I'm just started the second part and write down what my first approach is.
1. Tiering the system.
Since we have to get access to WEB and simple GUI application I suggest two points of entry to the system. One through WEB-container and another through RMI-based front controller. Both then talks to a BusinessDelegate that in rurn calls functional methods of SessionFacade. SessionFacade finally uses EntityBeans or DAO.
I guess the layout is more or less standard and doesn't have questionable points. The single one though is comunication of Java GUI application. I found RMI-based comunication is compromise one.
2. Object/class architecture.
After long reading of discussions regarding segment/flight/equipment meaning I came to the next schema.
[ some text removed by Ajith Kallambella ]
Customer, Flights and Itinerary are good candidates for being EntityBeans but it has own pros and cons. This part I haven't reckoned yet.
What do u think regarding my approach. All ideas are welcome!
[ May 29, 2003: Message edited by: Ajith Kallambella ]