The problem Airline Booking System solves

Its just a simple airline boking system, similar to currently available options, made completely in JAVA. Objective was to get hands dirty in OOM in JAVA, while implementing basic functionalities required in a booking system.
Options like create account, login,guest login(where booking permisions are denied). Select flight options across cities based on requirement like cost, time of departure, time of arrival, and Select preffered seats for the passengers flight is being booked.

Challenges I ran into

Main challenge in this simple project was only to get a proper UseCase and class diagrams to properly implement the idea with OOM rather than procedural.