Architecting and designing : UML 2.0 Lite : UML models : UML class diagrams : Ports
  
Ports
Ports are an important feature of the UML 2 specification for Class diagrams. System Architect enables you to retrofit UML 2 functionality back into UML, extending, not replacing the functionality. This differs from features also available through System Architect's UML 2 plugin component. You can model Ports in UML. The UML Class and Object definitions are enhanced with a Ports property, in the Ports List tab. Only these definition types can have Ports attached to them.
Ports are named interaction points of an active Class. They specify the implemented interface (realized) and the needed interfaces from other Classes (required). The Port definition has two properties, Required Interface and Realized Interface, each used to specify Class Interfaces. On the diagrams, you place the Port symbol on a Class or Object symbol, and then add Required Interfaces and/or Realized Interface in the Class definition.
Attaching a port to a class
1 Create or use an existing Class diagram in an encyclopedia configured with the UML property set (that is, UML 2).
Note UML 2 is a distinct property set in the encyclopedia Property Configuration set which is only available with the UML 2 plugin installed.
2 Click the Ports icon on to toolbar and attach it to the edge of a Class or Object symbol. You can attach the Port anywhere on the border of the Class or Object symbol.
3 Enter a Port name and click OK.
4 Click the Interfaces tab to specify Required Interfaces and/or Provided Interfaces. You can also specify these later on by editing the Class definition. The way the symbols are displayed on the diagram is based on the following factors:
A Realized Interface symbol is represented by a line from the Port leading to a full circle.
A Required Interface symbol is represented by a line from the Port leading to a half circle.
5 Click OK to close the Port definition. The Port symbols display on the diagram according to the options you selected above.
System Architects support for ports in UML
Diagram symbols that represent the same Class (for example, Objects) are also updated as Ports are added or removed. For example, suppose you draw a Class named 'Reception' and attach a Port named 'Port_1' to it. Then you draw an Object symbol that is defined by the same 'Reception' Class. The new Object symbol is also shown with the Port named 'Port_1' attached to it.
You can connect related Ports on different Classes with a Port Link line symbol—signifying the Class that provides an Interface to another Class that requires it. You can only draw Port Link symbols between Ports.
You can double-click on Port symbol to open its definition.
You can see the Ports attached to a Class in the Port List tab of the Class definition, and add new Ports or attach existing Ports to that Class definition.
As you add or remove Ports from a Class or Object symbol, the definition for that symbol is updated automatically to reflect those additions or removals.
You cannot resize Port Symbols. They stay the same if you resize the Class they are attached to and they keep the same relative position (e.g. 25% from the top on the right side).
If you use the Display According to Stereotype option for a Class the Port symbol is not shown, although lines extending from it are shown.
If a Class definition has Interface as its Stereotype, the Ports List tab and the Ports within it are not shown in the Class definition.
A Class or Object symbol cannot use the same Port definition multiple times.
You cannot add a Port symbol to diagram unless you attach it to a Class or Object symbol.
Note If you installed the UML 2 plugin for System Architect, you can find related information on how Ports work on UML 2 Class diagrams. Launch the main System Architect help and expand the table of contents books UML Modeling > UML 2 > Class Diagrams > Ports.
See also
UML class diagrams