1. SYS366
Documenting Use Cases

2. Use Case Specifications
For each use case in a use case diagram, need to describe, in detail, how the use case works = “a use case description or specification”

3. Use Case Specification
A use case specification describes the interaction between the actor and the system – it describes the steps, in sequential order, that a use case must do to fulfill a goal

4. Use Case Specification
A use case specification must include:
Who the actors are and how many of them are interacting with the system at any point in time
What data is used and how
All success and failure logic

5. Use Case Specification
A use case can have many paths through which it’s goals are accomplished – each path is know as a scenario
Each scenario can represent success logic or failure logic
A scenario is ONE PATH through a use case

6. Use Case Specification
Scenario is shown in a table format:
One column for Actor
Identify the actors who are involved in the scenario
One column for Scenario Description
Describe, in order, the steps that are done to complete the scenario
Written as a dialog between the actor and the system
Described using the Casual Use Case Specification Template

7. User Interface Design
The process of designing the overall sequences that users follow to interact with an information system
The sequence in which information is displayed to and obtained from the user
Understanding how the user will interact with the system

8. User Interface Design
Whether a success or failure logic, interface will be the same
Need to visualize the steps through the use case
Example: Rent A Video

9. Use Case Specification
Interface for Rent A Video use case might look like:
Rent Video - X
Customer Id:
Name: Phone #: Outstanding Balance:
Address:
Video ID
Title
Cost
Video Id:
Add
Method Of
Payment:
Subtotal:
Taxes:
Total:
Amount Paid:
Credit Card No:
Exp Date:

10. Use Case Specification
Ie. Rent A Video use case
Some possible scenarios could be:
Pay by credit card (normal logic)
Pay by debit card (normal logic)
Pay by cash (normal logic)
Credit card invalid (exception logic)

11. Use Case Descriptions
Sample Use case description for Rent A Video

12. Introduction to Use Cases
Carl’s OutDoors is a small business that rents various types of equipment for outdoor trips. Equipment such as camping equipment and canoes are rented. They also sell equipment for camping and canoeing and they organize outdoor adventure trips. Carl’s business has become very successful and he is having trouble keeping up with the growth. He needs to upgrade the system he currently has to handle the growing number of customers.
Carl has asked you to help with the rental part of his business. Customers want to rent either camping equipment or canoes. When they are finished, the customers want to return the equipment. On occasion it is necessary for a customer to exchange the equipment they’ve rented. This could be for a variety of reasons. Such as, the equipment is defective (i.e. a tent might have a hole in it causing it to leak; or a canoe isn’t big enough for the canoeists and their equipment). As new equipment is received each season, Carl makes old equipment available for sale. Usually it is a final sale but customers are allowed to return equipment that is defective (i.e. a tent might have a hole in it causing it to leak; or a canoe that might have a hole in it as well causing it to let water seep in).

13. Introduction to Use Cases
Rent Equipment
Return Rental Equipment
Exchange Rental Equipment
Process A Sale
Make Equipment Available For Sale
Return Equipment

14. Use Case Descriptions
Sample Use case description for Make Equipment Available For Sale
Make Equipment Available For Sale - X
Equipment Id:
Equipment Name:
Equip ID
Name
Cost
For Sale?
y/n
Done

15. Use Case Descriptions Sample Use case description for Rate Movie- X
Movie Title
Add
Rating
Movie Title
Rating
Done