Component Diagrams

Component Diagrams

• Component diagrams fall under the category of an implementation diagram, a kind of diagram that models the implementation and deployment of the system
• Component diagrams become much more useful when used as architectural-level artifacts, to model the logical architecture of your technical or business/domain infrastructures
• A Component Diagram, in particular, is used to describe the dependencies between various software components such as the dependency between runtime files and source files.

Component

• A component is a physical code module
• Components can include both source code libraries and runtime files
• Components are high level aggregations of smaller software pieces, and provide a 'black box' building block approach to software construction

   

Interface

• Describes a group of operations/services used or created by components
• Usually shown using a lollipop notation

Dependency

• Used to model the relationship between two components. The notation for a dependency relationship is a dotted arrow, pointing from a component to the component it depends on.

        

• Component dependencies have compilation implications.
• Avoid circular dependencies.
• The dependencies have maintenance implications.
• Dependencies will let you know what may or may not be easily reused.
  The fewer components a single component depends on, the easier it is to reuse.

Example