Chapter 3 Building Structural Diagrams

Ports (OOM)

A port is created on the outside of a classifier and specifies a distinct interaction point between the classifier and its environment or between the (behavior of the) classifier and its internal parts.

Ports can be connected to:

a part via a delegation connector, through which requests can be made to invoke the behavioral features of a classifier
an interface via a require link, through which the port may specify the services a classifier provides (offers) to its environment as well as the services that a classifier expects (requires) of its environment.

A port can be created in the following diagrams:

Class Diagram (on a class)
Composite Structure Diagram (on a class, a part, or an interface)
Component Diagram (on a component or a part)

Ports in a class diagram

In the example below, the class TitleImpl2 contains the ports sql and stat, which are connected by require links to the interfaces java.math.stat2 and java.sql.connection2:

Ports in a composite structure diagram

In the example below, the internal structure of the class TitleImpl2 is shown in more detail, and demonstrates how ports can be used to specify interaction points between a part and its enclosing classifier:

Ports in a component diagram

In the example below, the use of ports to connect parts with an enclosing component is demonstrated: