Optimization algorithms for OCL constraint evaluation in visual models

Abstract

The growing importance of modeling and model transformation has attracted attention to create precise models and transformations. Visual model definitions have a tendency to be incomplete, or imprecise, thus, the definitions are often extended by textual constraints attached to the model items. Textual constraints can eliminate the incompleteness stemming from the limitations of the visual definitions. Object Constraint Language (OCL) is one of the most popular constraint languages in the field of UML, Domain Specific Modeling Languages, and model transformations. Efficient constraint handling needs the optimization of the constraints. Our research focuses on creating optimization algorithms for OCL constraint handling. This paper presents three algorithms that can accelerate the validation process, and thus, make the modeling more efficient. Proofs are also provided to show that the optimized and the unoptimized code are functionally equivalent, and the paper contains a simple case study to show the practica l relevance of the algorithms.