Artifact:
Actor
Actor
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An
actor
defines a coherent set of roles that users of the system can play when
interacting with it. An
actor instance
can be played by either an individual or an external
system.
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UML
representation:
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Actor
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Role:
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Analyst
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More
information:
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Guidelines: Actor
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Checkpoints: Actor
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Output from Activities:
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Find Actors and Use Cases
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Templates, Case-Study, Report..
The Word template can be bought through a template package. Case studies and reports are freely available in the table below.
Word
Template
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Case
Study
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Report
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Purpose
Different stakeholders use this artifact for different purposes:
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System analysts
— to define the system boundaries.
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User-interface designers
— to
capture characteristics
on human actors.
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Use-case authors
— to describe use cases and their
interaction with actors.
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Object analysts
— to realize use cases and their
interaction with actors.
Properties
Property Name
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Brief Description
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UML Representation
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Name
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The
name of the actor.
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The
attribute "Name" on model element.
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Brief
Description
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A
brief description of the actor's sphere of responsibility and what the actor
needs the system for.
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Tagged
value, of type "short text".
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Characteristics
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For
human actors: The physical environment of the actor, the number of users the
actor represents, the actor's level of domain knowledge, the actor's level
of computer experience, other applications the actor is using, and other
general characteristics such as gender, age, cultural background, and so on.
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Tagged
value, of type "formatted text".
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Relationships
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The
relationships, such as actor-generalizations, and communicates-associations
in which the actor participates.
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Owned
by an enclosing package, via the aggregation "owns".
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Diagrams
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Any
diagrams local to the actor, such as use-case diagrams depicting the actor's
communicates-associations with use cases.
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Owned
by an enclosing package, via the aggregation "owns".
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Timing
Actors are found and related to use cases early in the Inception phase, when
the system is scoped. The characteristics of the actors are described before the
user interface is prototyped and implemented.
Responsibility
The
system analyst
is ultimately responsible for managing
the actors. Although the designer role
will update the detailed information about each actor, the system analyst is
responsible for ensuring that:
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Each actor has the correct communicates-associations with the use cases
with which it
participates.
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Each actor is part of the correct generalization relationships.
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Each actor defines a cohesive role and is independent of other actors.
A
user-interface designer
is responsible for the integrity
of human actor details, ensuring that:
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Each actor captures the necessary characteristics required to build the
user interface.
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The local use-case diagrams describing the actor are readable and
consistent with the other properties.
Tailoring
Decide which properties to use and how to use them. In particular, you need to
decide at which level of detail the "Characteristics" property needs to be
described.
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