1. Brief Description
2. Flow of Events

   2.1    Basic Flow - Select Courses to Teach

   2.2    Alternative Flows

           2.2.1    No Courses Available

           2.2.2    Schedule Conflict

           2.2.3    Course Registration Closed

3. Special Requirements
4. Preconditions

   4.1    Login

5. Postconditions
6. Extension Points

This use case allows a professor to select the course offerings (date- and time- specific courses will be given) from the course catalog for the courses that he/she is eligible for and wishes to teach in the upcoming semester.

The actor starting this use case is the Professor. The Course Catalog System is an actor within the use case.

The use case begins when the professor selects the "select courses to teach" activity from the Main Form.

2.1     Basic Flow - Select Courses to Teach

1. The system retrieves and displays the list of course offerings the professor is eligible to teach for the current semester. The system also retrieves and displays the list of courses the professor has previously selected to teach.
2. The professor selects and/or de-selects the course offerings that he/she wishes to teach for the upcoming semester.
3. The system removes the professor from teaching the de-selected course offerings.
4. The system verifies that the selected offerings do not conflict (i.e., have the same dates and times) with each other or any offerings the professor has previously signed up to teach. If there is no conflict, the system updates the course offering information for each offering the professor selects.

2.2     Alternative Flows

2.2.1    No Courses Available

If in the basic flow the professor is not eligible to teach any courses in the upcoming semester the system will display an error message. The professor acknowledges the message and the use case ends.

If the systems find a schedule conflict when trying to establish the course offerings the Professor should take, the system will display an error message indicating that a schedule conflict has occurred. The system will also indicate which are the conflicting courses. The professor can either resolve the schedule conflict (i.e., by canceling his selection to teach one of the course offerings) or cancel the operation, in which case any selections will be lost and the use case ends.

2.2.3    Course Registration Closed

If, when the Professor selects "select courses to teach", registration for the current semester has been closed, a message is displayed to the Professor and the use case terminates. Professors cannot change the course offerings they teach after registration for the current semester has been closed. If a professor change is needed after registration has been closed, it is handled outside the scope of this system.

    3.    Special Requirements

There are no special requirements associated with this use case.

    4.    Preconditions

            4.1    Login

Before this use case begins the Professor has logged onto the system.

    5.     Postconditions

There are no postconditions associated with this use case.

    6.     Extension Points

There are no extension points associated with this use case.