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| This artifact captures system behavior that yields an observable result of value to those interacting with the system. |
| Domains: Requirements |
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Purpose
Use cases are used for the following purposes:
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to reach a common understanding of system behavior.
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to design elements that support the required behavior.
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to identify test cases.
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to plan and assess work.
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to write user documentation.
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Relationships
| Container Artifact |
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| Roles | Responsible:
| Modified By:
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| Tasks | Input To:
| Output From:
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Description
| Brief Outline |
A use case typically includes the following information:
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Name: The name of the use case.
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Brief Description: A brief description of the role and purpose of the use case.
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Flow of Events: A textual description of what the system does in regard to a use case scenario
(not how specific problems are solved by the system). The description is understandable by the customer. The
flows can include a basic flow, alternative flows, and subflows.
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Key scenarios: A textual description of the most important or frequently discussed scenarios.
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Special Requirements: A textual description that collects all requirements, such as non-functional
requirements, on the use case, that are not considered in the use-case model, but that need to be taken care of
during design or implementation.
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Preconditions: A textual description that defines a constraint on the system when the use
case may start.
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Post conditions: A textual description that defines a constraint on the system when the use cases
have terminated.
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Extension points: A list of locations within the flow of events of the use case at which
additional behavior can be inserted using the extend-relationship.
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Illustrations
Tailoring
| Reasons for not needing | A project may use alternative requirements practices (e.g. “The system shall…” statements) which could replace use
cases.
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| Representation Options |
The use case can be documented as just a use-case specification document, or can be incorporated in a use-case
model. Use cases, and parts of use cases, can also be captured in a requirements management tool.
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More Information
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