The Port Tool
is used to define port
types. Instances of these port types are static ports that can be used as part
of object symbols, and to which roles will attach. Ports allow additional
semantics or constraints on how objects can be connected. For example, we can
set a requirement for the Family Tree diagram that all parental relationships
must connect to the top edge of the Person symbol and all child relationships to
its bottom edge.
Ports can also have their own properties, which are used
primarily to set port-related constraints (see Section
2.1.8). Port types do not have symbols of
their own, but they are visualized by Connectables in object type symbols (for
more information about Connectables, see Section
3.2.10). A Port type can however have an
icon, for when it or its instances are shown in a list.
Figure 2–15. Port Tool.
