Exit point
An exit point is an element of a state machine. An exit point pseudostate is an exit point of a composite state. The exit point changes the "enter-exit-do" sequence.
An exit point is used to join an internal transition terminating on the exit point to an external transition emanating from the exit point.
An entry point belongs to a composite state (not to a region).
Symbol
The symbol of an exit point is a circle around a cross.
The symbol of an exit point is placed on the border of the containing composite state.
Symbol in context
Example 1
In the example above let's consider that 'Simple state 1' and its ancestors are active. The "enter-exit-do" sequence is the following without the exit points:
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Transition 'T1'
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Simple state 'Simple state 1' is exited
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Composite state 'Composite state 3' is exited.
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'T1' is executed.
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Simple state 'Simple state 2' is entered and executed.
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Transition 'T2'
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Simple state 'Simple state 2' is exited.
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'Composite state 2' and 'Composite state 1' are exited.
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'T2' is executed.
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Simple state 'Simple state 3' is entered.
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Example 2
In the example above let's consider that that 'Simple state 1' and its ancestors are active. The "enter-exit-do" sequence is the following with the exit points:
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Compound transition 'T1', 'T2'
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Simple state 'Simple state 1' is exited.
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Transition 'T1' is executed.
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Composite state 'Composite state 3' is exited
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Transition 'T2' is executed.
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Simple state 'Simple state 2' is entered and executed.
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Compound transition 'T3', 'T4'
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Simple state 'Simple state 2' is exited.
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Composite state 'Composite state 2' is exited.
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Transition 'T3' is executed.
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Composite state 'Composite state 1' is exited.
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Transition 'T4' is executed.
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Simple state 'Simple state 3' is entered and executed.
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Characteristics
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Composite states can contain multiple exit points.
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An exit point can have multiple incoming and outgoing transitions.
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When the exit point is contained by an orthogonal composite state, than it is handled as a join, else as a junction.
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Exiting a composite state via an exit point implies that the exit behavior of the composite state is executed after the action of the transition incoming the exit point.