Style Guidelines and Best Practices : Activity Chart Conventions : Data-, Control- and Information-Flows

Data-, Control- and Information-Flows

Flow lines, which represent either data flows or control flows, shall be drawn as solid lines. Dashed lines shall be avoided. Within Rational Statemate there is no difference in the handling of those flows and furthermore, different line styles might lead to confusion.

Principally you can use information-flows between external and internal activities as well as between internal activities. Only at the lowest level of decomposition the information flow from/to external activities should be split into its data/control elements. Flows between external activities and Control Activities generally should depict the explicit data/control information (see the following figure).

External and Internal Flow Lines
 

 

All internal flow lines shall flow in a clockwise direction, with the respective names on the left-hand side of the arrow direction. The names of external flows should be written in the external activity, not on the arrow that defines the data flow.

Junction Connectors should not be used. Use direct branching of flows instead.

Readability hint: When flows cross within a chart, only a “T” is a joint or fork while a “+” is simply a crossing line with no connection.