Lecture 9, Part 1:
Modelling Interactions
Jennifer Campbell
CSC340 - Winter 2007
CSC340 University of Toronto 2
Moving Towards Specifications
•What functions will the new system
provide?
– How will people interact with it?
– Describe functions from a user’s perspective
•UML Use Cases
– Used to show:
• the functions to be provided by the system
•which actors will use which functions
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UML Use Case Diagrams
Capture the relationships between actors
and use cases.
Campaign
Manager
Accountant
Staff contact
[BMF99]
Add a
new client
Change a
client contact
Record
client payment
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Notation for Use Case Diagrams
Actor
Place book order
Communication
association
System
boundary
Use case
[BMF99]
Customer
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Use cases and Actors
•Use case:
–a pattern of behavior that the new system is required
to exhibit
–a sequence of related actions performed by an actor
and the system via a dialogue.
•Actor:
–anything that needs to interact with the system:
•a person
•a role that different people may play
•another (external) system.
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Example: Staff Management
Add new
staff member
Add new
staff category
Calculate staff
bonuses
Change category
for staff member
Accountant
Change rate
for staff category
Staff
Management
System
