1. 1 Use case sample cs 236700

2. 2 System Overview  A new web-based front-end for an existing library  There is a global book info service  Typical actions Placing an order on a book Looking up a book Adding new clients Adding new books

3. 3 The actors  All entities which are outside our the system: Client Librarian Global Book Info DB  Internal entities are NOT actors: Library catalog DB Client DB uc-sample-1.mdl

4. 4 The use-cases  NewClient A new client joins the system  OrderBook Let a client place an order  NewBook A new book is added to the system  LookForABook Find a book/find a book details uc-sample-2.mdl uc-sample-3.mdl

5. 5 Relationships  Librarian vs. Client Is it true that every librarian is also a client? Yes – he can do everything a client does No – He does not have to pay for membership  Let’s assume that for the purposes of the system a librarian IS also a client  How do we express this in the use-case diagram? Using the “generalization” arrow uc-sample-4.mdl

6. 6 UC Description Name: “NewBook” Actors: Librarian, GlobalBookInfoDb Goal: Add a new book to the system Reference to requirements: … Pre-conditions System initiated Description 1.Librarian enters “Add New Book” page. 2.System displays “New book details” form. 3.Librarian fills the form and clicks on “submit”. 4.System retrieves additional details from the GlobalBookInfoDb. 5.System displays “Book added successfully” page. Post-conditions The new book is now listed in the library’s catalog Variations Book already in catalog … Exceptions GlobalBookInfoDb is not responding … Book not found on GlobalBookInfoDb