Date: 9 June 2001; Author: Shane Sendall (LGL-DI-EPFL)
LBB System
Use Case: check-out books
Scope: Library Book Borrowing System
Level: User Goal
Intention in Context: The intention of the User is to check-out books from a library. Only one User can check-out books at any one time.
Primary Actor: User (becomes Member once s/he has identified him/herself with the System)
Main Success Scenario:
1. User requests System to check-out books.
2. User identifies him/herself to System.
Step 3 is repeated for each book that is checked-out by Member.
3. Member registers book with System.
4. Member indicates to System that s/he has finished checking out books.
5. System records all books registered by Member as on loan, requests Printer to print out a receipt* for the session, and puts itself in a state to receive the next User.
Extensions:
2a. User fails to identifies him/herself with System: use case ends in failures.
3a. System informs Member that s/he has reached his/her maximum number of books allowed on loan; use case continues at step 4.
3||a. Member requests System to remove book from the books that are checked out:
3||a.1. Member identifies book to System.
3||a.2a. System identifies book and removes it from the list of books registered by Member; use case continues from where it was interrupted.
3||a.2b. System fails to identify book; use case continues from where it was interrupted.
(3-4)a. Member requests System to cancel check-out.
(3-4)a.1. System removes all books that were registered by Member, and puts itself in a state to receive the next User; use case ends in failure.
(3-4)b. System times-out waiting for input from Member:
(3-4)b.1. System removes all books that were registered by Member, and puts itself in a state to receive the next User; use case ends in failure.
Notes:
* normally a hyperlink to the document that contains data details and formats.