Use Cases

Wednesday, March 12, 2008

Individual Use Case - a procedure by which an actor uses a system.
Example: Indicate Course Priority
Use Case - a sequence of interactions between the actor and the system.
Example:
Populate Course List
1. In the Student Plan Builder Application a student right clicks a term and chooses option: "Register for classes"
2. That term's courses populate the course list in the AutoScheduler


Input Course Priority
1. click star amount next to course to indicate priority
2. repeat step 1 for all courses in term


Good uses cases:
use easy to understand language
are a view of functional requirements
are not ambiguous (source and target are identified)

Actor - a system, person or external entity that defines the system boundary

Alternate flows - should know exactly how to insert and return to the basic flow statement and have:
4 essential elements of an alternate flow:

Where it inserts itself
Under what conditions it runs
What is done written as you would for any other flow
Whether it returns, and to where, or terminates



Example:
Basic Flow: Indicate Availability
1. right click a time slot on the Availability Calendar
2. set availability status
3. click subsequent time slots that the user determines has same the same availability

Alternative Flow: Change Availability Status
1. If 3. from Indicate Availability already has a status previously set, the new status overrides.
2. The use case restarts at 2 in Indicate Availability

Labels: Technology