Rent Video Use Case

During lecture 22, I showed a picture of an activity diagram for a use case called Rent Video. The text of that use case appears below. Note: this example comes from the book "Requirements Analysis and System Design: Developing Information Systems with UML" written by Leszek A. Maciaszek, Pearson Education Limited, 2001. Note: The text below is not a word for word copy of the original. I have edited some of the text for clarity and brevity.

Rent Video
Summary A customer wishes to rent a video that is picked from the store's shelves or that have been previously reserved. Provided the customer has a non-delinquent account, the tape is rented out once the payment has been received. If the tape is not returned in a timely fashion, an overdue notice is mailed to the customer.
Actors Customer, Employee, Scanning device
Preconditions Video is available to be rented. Customer has a membership card. Scanning device is operational. Employee knows how to use rental system.
Main flow A customer asks an employee about video availability (including a reserved video) or picks one or more videos from the shelves. The videos and the membership card are scanned and any delinquent or overdue details are brought to the employee's attention. If the customer does not have a delinquent rating, then he/she can rent up to a maximum of eight videos. However, if the rating of the customer is "unreliable" then a deposit of one rental period for each video is requested. Once the amount payable is received, the stock is updated and the videos are given to the customer together with a receipt. The customer may pay by cash, credit card, or electronic transfer. Each rental record stores (under the customer's account) the check-out and due dates for each video together with the identification of the employee. A separate rental record is created for each rented video. The use case will generate an overdue notice to the customer if a video has not been returned within two days of the due date, and a second notice after another two days (and at that time the customer is noted as "delinquent").
Alternative flows
  • A customer does not have a membership card. In this case, the Maintain Customer use case may be activated to issue a new card.
  • An attempt to rent too many videos
  • No videos can be rented due to the customer's delinquent rating.
  • The video or membership card can not be scanned.
  • The electronic transfer or credit card payment is refused.
Postconditions Videos are rented out and the database is updated accordingly.
Kenneth M. Anderson, 2008.