Use-Case Diagrams and Specifications

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Use-Case Diagram Overview

Use-case diagrams present a high-level view of how a system is used as seen from an outsider's (or actor's) perspective. These diagrams graphically depict system behavior (also known as use cases). A use-case diagram may depict all or some of the use cases of a system.

A use-case diagram can contain:

• Actors ("things" outside the system).
• Use cases (system boundaries identifying what the system should do).
• Interactions or relationships between actors and use cases in the system including the associations, dependencies, and generalizations.

Use-case diagrams can be used during analysis to capture the system requirements and understand how the system should work. During the design phase, use-case diagrams can be used to specify the behavior of the system as implemented.

You can create or display a use-case diagram in one of three ways:

• Click Browse > Use Case Diagram.
• On the toolbar, double-click the use-case diagram icon.
• In the browser, double-click the use-case diagram icon.