Use Case Diagram

Use Case diagrams capture Use Cases and the relationships between Actors and the subject (system).

Use to

Describe the functional requirements of the system
Describe the manner in which outside things (Actors) interact at the system boundary
Describe the response of the system.

Example Diagram     Example Use Case Diagram

Tools

Select Use Case diagram elements and connectors from the Use Case pages of the Toolbox.

Click on the following elements and connectors for more information.

Use Case Diagram Elements

Use Case Diagram Connectors

e_Actor

c_Use

e_UseCase

c_Associate

e_testcase

c_Generalize

e_Collaboration

c_Include

e_collaboration_use

c_Extend

e_BoundaryBox

c_Realize

e_Package

c_Invokes

 

c_Precedes

Notes

Invokes and Precedes relationships are defined by the Open Modeling Language (OML); they are stereotyped Dependency relationships
Invokes indicates that Use Case A, at some point, causes Use Case B to happen
Precedes indicates that Use Case C must complete before Use Case D can begin

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