Component diagrams

Structural Modeling Diagrams

Component diagrams

In the Unified Modeling Language, a component diagram depicts how a software system is split up into physical components and shows the dependencies among these components. Physical components could be, for example, files, headers, link libraries, modules, executables, or packages. Component diagrams can be used to model and document any system’s architecture. Note that components are types and only executable components may have instances.

Components are similar in practice to package diagrams, as they define boundaries and are used to group elements into logical structures. The difference between package diagrams and component diagrams is that Component Diagrams offer a more semantically rich grouping mechanism. With component diagrams all of the model elements are private, whereas package diagrams only display public items.

Representing Components

Components are represented as a rectangular classifier with the keyword «component»; optionally the component may be displayed as a rectangle with a component icon in the right-hand upper corner.

Assembly Connector

The assembly connector bridges a component’s required interface (Component1) with the provided interface of another component (Component2); this allows one component to provide the services that another component requires.