Consider the following use case description of issue book use case. Introduction: This use case documents the steps that must be followed in order to get a book issued. Actors Administrator Library Staff Librarian Precondition: The administrator/library staff must be logged onto the system before the use case begins. Postcondition: If the use case is successful, a book is issued to the student to the student/faculty/employee and the database is updated, else the system state remains unchanged. Event Flow Basic Flow 1. The student/faculty/employee membership number is read through the bar code reader. 2. The system displays information about the student/faculty/employee. 3. Book information is read through the bar code reader. 4. The book is issued for the specified number of days and the return date of the book is calculated and stamped on the book. 5. The book and student/faculty/employee information are saved into the database. Alternative Flows Alterr ive Flow 1: Unauthorized student/faculty/employee If the system does not validate the student/faculty/employee membership number (due to membership expiry or any other reason), then an error message is flagged, and the use case returns to the beginning of the basic flow. Alternative Flow 2: Account is full If the student/faculty/employee ha requested a book and the account if full i.e., he/she has already maximum number of books issued on his/her name, then the request for issue is denied and the use case ends. Alternative Flow 3: User exits This allows the user to exit at any time during the use case. The use case ends. Special requirement None Associated use case Login