Subject: Object Oriented Modeling and Design

Difficulty: Medium

Marks: 4 Marks

Use case diagram:-It shows a set of use cases and actors and their relationships. a use case is a description of a set of sequences of actions that a system performs to get an result to tan actor. It describes a set of sequences in which each sequence represents the interaction of the things outside the system with the system itself. It represents functional requirements of system. For example, for ATM system validating pin for the customer is a behavior of a system which can be shown as use case. It addresses the static use case view of a system. These are important in organizing and modeling the behaviors of a system.

Common uses of use case diagram:

• To model the context of a system:- modeling the context of a system involves drawing a line around the system and representing actors lie outside the system and interact with it. In use case diagram actors and the meaning of their roles is represented.
• To model the requirements of a system:- modeling the requirements of a system involves specifying what that system should do without respect to how that system should do it.

Notations:-

Use case: - It is shown with ellipse.

Association: - It is shown with solid line.