Identify the four fundamental modeling elements of a use case diagram.
Use Case Diagram
The use case model has three components. The first component, and the only one actually defined by the UML, is the use case diagram.
To supplement the diagram, it is almost always necessary to add a use case narrative. Once a use case is fully described, it is possible to dissect it into scenarios, or test cases.
Remember that although diagrams are extremely valuable and provide substantial information, they nearly always require some form of explanation to put them into context and ensure their proper interpretation.
Use case diagram
Four modeling elements make up the use case diagram: system, actors, use cases, and associations.
Each association becomes a dialog that must be explained in a use case narrative. Each narrative in turn provides a set of scenarios that function as test cases when evaluating the design and implementation of the use case.
In the next lesson, you will learn about the use case system element.