A condition or situation during the life of an object during which it satisfies some condition, performs some do activity, or waits for some event.

See also action, activity, composite state, do activity, entry activity, exit activity, final state, internal transition, pseudostate, state machine, submachine state, transition.


An object holds a series of states during its lifetime. When an object satisfies the condition of a state, the state is said to be active. The active state configuration is the set of states that are active at any point in time. If it contains more than one state, there is concurrency within the object. The number of active states can change during the life of an object due to forks or joins of control.

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