Chapter 6 – Use Case
- Use cases are text stories of some actor using a system to meet goal.
- Example: Process Sale: A customer arrives at a checkout with items to purchase. The
cashier uses the POS system to record each purchased item. The system presents a running
total and line-item details. The customer enters payment information, which the system
validates and records. The system updates inventory. The customer receives a receipt from
the system and then leaves with the items.
- Uses cases often are needed to be more detailed or structured and the essence is discovering
and recording functional requirements by writing stories of using a system to fulfill user goals
6.2 Definition: What is Actor, Scenarios, and Use Cases
Scenario: is a specific sequence of actions and interactions between actors and the system
Use case: is a collected of related success and failure scenarios that describe the actor using a system to
support a goal
- It contains the main success scenario and alterative scenarios
6.3 Use Cases and the Use-Case Model
- The Use-Case Model is not only requirement artifact in the UP. There are also the
Supplementary specifications, Glossary, Vision, and Business Rules.
- The use case model may optionally include a UML use case diagram to the name of use cases
and actors and their relationships, which is the context diagram of the