This part of the book covers a collection of mistakes often found in use-case models. This collection should be used to detect that something may be wrong in the model. Although rare, there may be a good reason why a model matches one of these erroneous models and still be correct.
All chapters in this part are organized in the same way:
Name of mistake—. A descriptive name of the error in a few words
Fault—. A short description of the mistake
Incorrect model—. A use-case model illustrating the mistake
Discussion—. A discussion on why this is an incorrect model
Way out—. Hints on what to do to correct the incorrect model
The chapters presenting the mistakes are sorted alphabetically within this part.
Chapter 37. Alternative Flow as Extension: Modeling an alternative flow of a use case as an extension of that use case.
Chapter 38. Business Use Case: Modeling a business process as a system use case.
Chapter 39. Communicating Use Cases: Modeling two use cases with an association between them, implying that the use cases communicate with each other.
Chapter 40. Functional Decomposition: One large use case with include relationships to a set of inclusion use cases, each modeling a subfunction of the large use case.
Chapter 41. Micro Use Cases: Modeling single operations performed by the users as separate use cases, resulting in a use-case model consisting of a large number of very small use cases.
Chapter 42. Mix of Abstraction Levels: A use-case model containing use cases defined at different levels of abstraction.
Chapter 43. Multiple Business Values: Incorporating too much in a single use case by capturing several goals or business values in one use case.
Chapter 44. Security Levels with Actors: Capturing the security levels restricting who may use the different services of the system only by defining actors corresponding to the security levels.