Use Case Extends Link

Use the Extends link to show that one use case extends the functionality of another use case at specific Extension Points.

How do I set up a link on my diagram?

How do I set up Extension Points?

The property page for the extends link will list the extension points of the base use case.  Check-off the extension points that apply to your extends link.  In the example below, the Take Cash Payment extends Take Payment at the extension point Cash:

How do I open a link's property page?

Then, the link caption on the diagram shows the extension points that you selected.

Related Topics:

• Use Case Extension Points

• Use Case Diagram

• Sample Use Case Diagram

• Introduction to the UML