Create a use case model (i.e., use case diagram and descriptions) for a university library system.

Books and member card are submitted to the circulation clerk. Before someone can borrow a book, he or she must show a valid ID card, which is checked to ensure that it is still valid against the database maintained by the library. If the client is not a member, a membership card for the client is created. The members personal information such as address and phone number is validated against the client file. If the club member has indicated an information change, the client information is revised. For each book being checked out, the circulation clerk scans the book. The system records the return date. The system must also check to ensure that the borrower does not have any overdue books or unpaid fines before he or she can borrow another book. The overdue books must be returned and the unpaid fine must be paid. If the book is not available, an interlibrary loan application is made. The client takes the books and leaves the library.

The system maintains the books owned by the library. Every Monday, the system sorts the borrowed books by return date. It prints the list of the people with overdue books. Postcards are mailed to them. If a book is overdue by more than two weeks, a fine will be imposed and a librarian will telephone the borrower to remind him or her to return the book(s). Sometimes books are lost or are returned in damaged condition. The manager must then remove them from the database and will sometimes impose a fine on the borrower.

A client can extend the book loan (in phone or in person). Books and member information are submitted to the circulation clerk and validated. For each book being extended, the circulation clerk adjusts the loan. The system records the new return date. If the book is on the call list, the loan cannot be extended.