Functionality Availability
This feature is available in Standard, Professional, Architect, and Enterprise editions.
The Robustness Analysis involves analyzing the narrative text of use cases, identifying a first-guess set of objects that participate in those use cases and classifying the objects based on the roles they play.
- Boundary or Interface objects are what actors use in communicating with the system.
- Entity objects are mostly objects from the domain model.
- Control objects (known as controllers because they often are not real objects) serve as the "glue" between boundary objects and entity objects.
The Robustness Analysis acts as a preliminary design within the project lifecycle, providing the missing link between an analysis and a detailed design.
Four basic rules apply:
- Actors can only talk to the boundary objects.
- The boundary objects can only talk to the controllers and actors.
- The entity objects can only talk to the controllers.
- The controllers can talk to the boundary objects and entity objects, and to other controllers, but not to the actors.
Both the boundary objects and entity objects are nouns; the controllers are verbs. Nouns cannot talk to other nouns, but verbs can talk to either nouns or verbs.