Activity Diagram - Partition (Swimlane) Notation

UML Tutorials - Herong's Tutorial Examples

∟Activity Diagram - Partition (Swimlane) Notation

This section describes the Partition (Swimlane) Notation used in a UML Activity Diagram. A Partition Notation represents a group of actions and objects that share some common properties.

A Partition (Swimlane) Notation is a graphical notation used in a UML Activity Diagram to identify a group of actions and objects that share some common properties.

A Partition (Swimlane) Notation is drawn as two parallel lines with the partition name as one end. Any actions and objects that are located within the two lines are considered to be in the group. If an action or object may located on the border of multiple partitions, is considered to be in multiple groups.

Partitions can be nested to form a hierarchy of partitions.

For example, actions and objects in an order processing activity can be divided into 3 groups: Order Department action group, Accounting Department action group, and customer action group, based on action ownerships. These groups can be drawn as Partition Notations in a UML activity diagram as shown below: