Flow charts decompose a system into actions that
correspond to activities. These diagrammatic elements, called actions,
are member function calls within a given operation.
In
contrast to normal states (as in statecharts), actions in flow charts
terminate on completion of the activity, rather than as a reaction
to an externally generated event.
Each action can have an entry action, and must have
at least one outgoing action flow. If the action has several outgoing
action flows, each must have its own guard condition.
During code generation, code is derived from the
actions on a flow chart.
Actions have the following constraints:
- Outgoing control flows can include only guard conditions.
- Actions have non-empty entry actions.
- Actions do not have internal action flows or exit
actions, nor do activities.
- Outgoing action flows on actions have no triggering
events.