Consider the specification of a (fragment of) information system for a sauna booking system, which includes

the following.

There are ordinary customers and premium customers. Contact information is stored for all

customers.

A customer can create bookings for him/herself.

A customer can search for all his/her current bookings, and possibly, in addition to the search, get

the details of a specific booking, returned by the search.

Once a customer has obtained the details of a certain booking, from there he/she can delete said

booking.

A premium customer (and only premium customers) can book a free drink for each of his/her

bookings, but only upon creation of said booking.

Draw a UML use-case diagram as well as an UML essential class diagram (without attributes and operations)

for the above specification. Produce CRC (Class-Responsibility-Collaborator) cards for the relevant classes.

(20 marks)