Improving UML's Definition of the Use-Case Class

摘要

UML is shown to contain two defects concerning the use-case class that originated in OOSE. These defects are: (1) the use-case class and its instances are unusually defined, and (2) a conjecture that is against the definition of a use case is introduced without any reason. These defects have been causing unnecessary confusion in UML's specification of the use-case class. An object-oriented real-world model is built that represents a typical situation of the employment of a use case in the analysis and design stages, and then another specification of the use-case class is constructed, which successfully solves the problems.