A Usable Interchange Format for Rich Syntax Rules Integrating OCL, RuleML and SWRL

Rules are becoming increasingly important in business modeling and requirements engineering, and as a high level programming paradigm. In the area of rule modeling there are different developer communities like UML modelers and ontology architects. The former use rules in business modeling and in software development, while the latter use rules in collaborative Web applications. Each of them is using different rule languages and tools. Since a business rule is the same rule no matter in which language it is formalized, it is important to support the interchange of rules between different systems and tools. This paper presents an interchange format for rules integrating the Rule Markup Language (RuleML), the Semantic Web Rule Language (SWRL) and the Object Constraint Language (OCL). These languages provide a rich syntax for expressing rules. This means that they support conceptual distinctions, such as distinguishing different types of terms and different types of atoms, which are not present in standard predicate logic. The interchange format is usable in the sense that it allows structure-preserving markup of all constructs of these different languages and does not force users to translate their rule expressions to a completely different language paradigm such as having to transform a function into a functional predicate. In the case of OCL rules this is achieved by developing a logical reconstruction of the ’unlogical’ original OCL metamodel. We consider three kinds of rules in this paper: integrity rules, derivation rules and production rules. We define rule concepts with the help of MOF/UML, a subset of the UML class modeling language proposed by the Object Management Group (OMG) for the purpose of ’meta-modeling’, i.e. for defining languages conceptually on the level of an abstract (semi-visual) syntax.