A class may be eliminated altogether from the model. This happens when:
The class does not have any structure or behavior
The class does not participate in any use cases
In particular, examine control classes. Lack of sequencing responsibility may lead to the deletion of the control class. This is especially true if the control class is only a pass-through—that is, the control class receives information from a boundary class and immediately passes it to an entity class without the need for sequencing logic.
In the ESU Course Registration System, initially we would create a control class for the Select Courses to Teach use case. This use case provides the capability for professors to state what course offerings they will teach ...