As discussed in Chapter 2, a
swimlane is a
visual region in an activity diagram that indicates the element that
has responsibility for action states within the region. For example,
the project management system may have the following swimlanes, which
are illustrated in Figure 8-6:
- Project Manager
Shows the action states that are the responsibility of a project
manager. The swimlane makes it obvious that the project manager is
responsible for entering data, thus the rather cumbersome action
state name of Project Manager
Enters Data may be shortened to
- Project Management System
Shows the action states that are the responsibility of the project
management system. Again, because the swimlane makes it obvious who
(or what, in this case) is generating information, the rather
cumbersome action state name of Project
Generates Information may be
shortened to Generate Information.
Shows the action states that are the responsibility of a printer.
Because of this swimlane, the rather cumbersome action state name of
Information may be shortened to
Notice how the use of swimlanes allows me to rename the action states
to omit the responsible element for each action state.
In the UML, a swimlane is shown as a visual region separated from
neighboring swimlanes by vertical solid lines on both sides and
labeled at the top with the element responsible for action states
within the swimlane. Figure 8-6 shows the swimlanes
associated with the project management system.
Figure 8-6. Swimlanes