Formalizing the Evaluation of OCL Constraints
Gergely Mezei, Tihamér Levendovszky, Hassan Charaf · 2007
Domain-specific modeling has growing importance in many fields of software enginering, such as modeling control flows of data processing, or in man-machine systems. Customizable language dictionary and customizable notations of the model elements offered by domain-specific technologies make software systems easier to create and maintain. However, visual model definitions have a tendency to be incomplete, or imprecise; the definitions can be extended by textual constraints attached to the model items. Textual constraints can eliminate the incompleteness stemming from the limitations of the structural definition as well. The Object Constraint Language (OCL) is one of the most popular constraint languages in the field of UML and Domain Specific Modeling Languages. OCL is a flexible, yet formal language with a mathematical background. Existing formalisms of OCL does not describe dynamic behavior of constraints. Our research aims at creating an OCL optimization solution and prove its correctness formally. However, the shortcomings of the existing formalism has led us to create a new formalism. The paper presents OCLASM, a new formalism for OCL, which can describe both the semantics and the dynamical behavior of the language constructs, thus, it is capable of describing proofs of optimization algortihms. OCLASM is based on the Abstract State Machines technique.