Guidelines: Actor-Generalization in the Business Use-Case Model
Several business actors can play the same role in a particular business use
case. Thus, both a Business Traveler and a Tourist are seen as the same external
entity by the business use case that handles the check-in. The shared role is
modeled as a business actor, Passenger, inherited by the two original business
actors. We show these relationships with generalizations.
The actors Business Traveler and Tourist inherit all the
attributes of a Passenger. Thus, both these actors can act as Passengers.
On the other hand, one business user can play several different roles in
relation to the business, which means that the user can correspond to several
business actors. If this is the general behavior of this kind of user, the model
may become clearer if the user is represented by one business actor who inherits
several business actors. Each inherited business actor represents one of the
user?s roles relative to the business.
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