Car Park

A small domain modeling / coding exercise.

Goals

• Come up with a domain model as straight forward/simple as possible.
• Implement incrementally.
• Code should tell the story. Use layers of abstraction (what it does vs. how it's done).

Requirements

• Before entering the car park, motorists must take a ticket.
• Entry shows red signal, has closed barrier.
• Entry opens barrier, shows green signal after a ticket was requested.
• Entry shows red signal, closes barrier after vehicle entered the car park.
• Entry shows whether space is available or not.
• Entry only returns ticket if space is available.
• Entry only returns ticket if vehicle is standing in front of it.
• Parking fee has to be payed at the pay station.
• Parking is free for the first 30 minutes.
• After the first 30 minutes, the parking fee is 1 euro per hour.
• Exit shows red signal, has closed barrier.
• Exit accepts ticket and shows green signal / opens barrier, if parking fee was payed.
• Exit shows red signal, returns ticket is parking fee was not payed.
• Exit shows red signal, closes barrier after car left the car park.