System Development
Of-the-Month Club (OTMC) is an innovative firm in Ghana with head-office in Accra and branch offices
in Kumasi, Sunyani, Tamale and Takoradi. OTMC sells memberships to people who have an interest
in certain products. People pay membership fees for one year and each month receive a product by
mail. For example, OTMC has a coffee-of-the month club that sends members 250 kilograms of
special coffee each month. OTMC currently has six memberships (coffee, chocolate, wine, beer,
flowers, and computer games), each of which costs a different amount. Customers usually belong to
just one, but some belong to two or more. When people join OTMC, the telephone operator records
the name, mailing address, phone number, e-mail address, credit card information, start date, and
membership service(s) (e.g., coffee). Some customers request a double or triple membership (e.g.,
250 kilograms of coffee, 4 cartons of beer). The computer game membership operates a bit differently
from the others. In this case, the member must also select the type of game (action, arcade,
fantasy/science fiction, educational, etc.) and age level. OTMC is planning to greatly expand the
number of memberships it offers (e.g., video games, movies, toys, cheese, fruit, vegetables), so the
system needs to accommodate this future expansion. OTMC is also planning to offer three-month and
six-month memberships.
Requirements:
(a) Provide a formalized system’s Object model of OTMC’s business transactions and an instance
diagram of the model with the following:
(i) The head-office coordinates transactions and manages activities of all the 4 branches
(ii) Membership types by clients and the fee payable
(iii) Transactions involving products mailed to members are done at all branches
Explain the Object model drawn and justify why models can assist the analysis and design
processes of the system. [20 marks]
(b) Create a Use Case diagram for the object model in question (a) above and justify why Use
Cases are critical in eliciting user and system requirements. [10 marks]