Normal use cases description

A normal use case includes a Title, a Primary Actor field, a Participants field, a Goal field, a Precondition, a Postcondition, a sequence of Steps, a set of Any Extensions, and a set of Extension Points. The description of these elements is as follow.

• Title: a label that uniquely identifies the use case within the use case model.
• Scope: specifies what system is being considered black box under design (e.g. whole business, system, sub-system, function).

  The different possible values for scope are defined in property file traits.properties.

• Level: is the use case level of detail.

  The different possible values for scope are defined in property file traits.properties.

• Primary Actor: the actor that initiates the use case.
• Participants: other actors participating in the use case.
• Goal: a statement of the primary actor expectation at the successful completion of the use case.
• Precondition: a condition that must hold before an instance of the use case can be executed.
• Postcondition: a condition that must be true at the end of a 'successful' execution of an instance of the use case.
• Steps: a sequence of steps. Each step references a use case step operation.

  A use case step operation may be a concept operation instance, a branching statement or a reference to an included use case.

  A step may also include a set of step extensions each defining an alternative behavior following the step.

• Any Extensions: a set of step extensions that applies to all the steps in the use case.
• Extension Points: a set of locations in the use case steps where additional behaviors defined in extension use cases might be inserted.

A use case description can be seen as a two parts description with:

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a static part that includes the use case Title, Primary Actor, Participants, Goal, Precondition and Postcondition fields, and

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a dynamic or procedural part that consists of the use case Steps.