A specification of how messages are exchanged over time between roles within a context to perform a task. An interaction specifies a pattern of behavior. The context is supplied by a classifier or collaboration. In an instance of an interaction, objects are bound to its roles and a particular trace of messages among objects must be consistent with the specification.


A reusable arrangement of connected objects can be specified using a structured classifier or a collaboration. Each object is a part within a well-defined context.

Objects or other instances communicate within a context to accomplish a purpose (such as performing an operation) by exchanging messages. The messages may include signals and calls, as well as implicit ...

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