Use Cases
- When we build systems/applications that are usage-centric (Example: Database-oriented, UI-centric applications), the first step is to analyze its requirements by organizing them around the different ways the features are used by the users
- Once the analysis results are documented, they will be used as inputs to design and implement the solution
- The different ways in which a mobile phone is used by users
Make calls
Receive calls
Send message/image
Receive message/image
Store details of contacts (store, edit, retrieve, delete)
Capture a picture
Send an e-mail
Receive an e-mail
What is each item in the list?
Each is:
- A way of using a system to do something useful or valuable to the user
- A way for a user to interact with the system to achieve a goal
- A valuable end-to-end service provided by a system to a user
- Each is called a 'use case’
- Graphically, a use case is represented as an ellipse
What Use case are NOT?
- Use cases are not functional decomposition
Example: Finding the districts of a state, finding the role of a user, finding age based on date of birth.
- Steps of an end-to-end service is not a use case
Example: Adding an item to a shopping cart is not a use case; instead, 'Place order' is.
- Each alternative is not a use case
Example: Remove an item from shopping cart, changing the quantity or shipping/payment info, etc.
