Chapter 4 Extending your Models with Profiles

Using Profiles: a Case Study

To illustrate the concept of profile, you are going to build an extended model definition for an OOM. This model extension will let you design a robustness diagram.

Robustness diagram

The robustness diagram is used to get across the gap between what the system has to do, and how it is actually going to accomplish this task. In the UML analysis, the robustness diagram is between use case and sequence diagram analysis. It allows you to verify that the use case is correct and that you have not specified a system behavior that is unreasonable given the sets of objects you have. The robustness diagram also enables to verify if no object is missing in the model.

You are going to build a robustness diagram using the communication diagram in the OOM, together with an extended model definition containing a user-defined profile. This profile contains the following extensions:

Stereotypes for objects
Custom tool and symbol for each object stereotype
Custom checks for instance links
Generated file to output a description of messages exchanged between objects

You will follow this case study to create a new extended model definition. This extended model definition corresponds to the resource file Robustness.XEM, delivered by default and located in the \Resource Files\Extended Model Definitions folder of the PowerDesigner installation directory.