Flows ( OOM)

A flow is a route the control flow takes between objects . The routing of the control flow is made using guard conditions defined on flows. If the condition is true, the control is passed to the next object.

A flow can be created in the following diagrams:

Activity Diagram
Interaction Overview Diagram

A flow between an activity and an object node indicates that the execution of the activity puts an object in a specific state. When a specific event occurs or when specific conditions are satisfied, the control flow passes from the activity to the object node. A flow from an object node to an activity means that the activity uses this specific state in its execution. In both cases, the flow is represented as a simple arrow.

In the following example the flow links Process Order to Ship US Postal Ground:

A flow can link shortcuts. A flow accepts shortcuts on both extremities to prevent it from being automatically moved when a process is to be moved. In this case, the process is moved and leaves a shortcut, but contrary to the other links, the flow is not moved. Shortcuts of flows do not exist, and flows remain in place in all cases.

The following rules apply:

Reflexive flows (same source and destination process) are allowed on processes.
Two flows between the same source and destination objects are permitted, and called parallel flows.

Note: When flows are compared and merged by the Merge Model feature, they are matched by trigger event first, and then by their calculated name. When two flows match, the trigger actions automatically match because there cannot be more than one trigger action.