A discrete entity with a well-defined boundary and identity that encapsulates state and behavior; an instance of a class.

See also class, identity, instance, object flow.


An object is an instance of a class, which describes the set of possible objects that can exist. An object can be viewed from two related perspectives: as an entity at a particular point in time with a specific value and as a holder of identity that has different values over time. Both views can coexist in a model, but not in the same object or class. The first view is appropriate to a snapshot, which represents a system at a point in time. An object in a snapshot has values for each of its attributes. An object is attached to a collection of links that connect ...

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