An OCL - based semantics of system state modification primitives

Abstract

An object oriented system can be manipulated at a conceptual level by system state manipulation primitives. The possible manipulations include either queries or modifications to the state of system. Modification primitives are used to describe the behavior of more complex state manipulations, such as system level operations. A well defined semantics for these primitives is critical for a precise specification of system operations. In this paper, we present the semantics for the most common system state modification primitives. Their semantics will be specified by pre and post-conditions expressed in OCL and using the UML metamodel as the model of systems for the OCL expressions. Every constraint was validated using the USE tool.