Abstract. Using ontologies in software applications is a challenging task due to the chasm between the logics-based world of ontologies and the object-oriented world of software applications. The logics-based repre-sentation emphasizes the meaning of concepts and properties, i.e., their semantics. The modeler in the object-oriented paradigm also takes into account the pragmatics, i.e., how the classes are used, by whom, and why. To enable a comprehensive use of logics-based representations in object-oriented software systems, a seamless integration of the two paradigms is needed. However, the pragmatic issues of using logic-based knowledge in object-oriented software applications has yet not been considered suffi-ciently. Rather, the pragmatic issues that arise in using an ontology, e.g., which classes to instantiate in which order, remains a task to be care-fully considered by the application developer. In this paper, we present a declarative representation for designing and applying programming ac-cess to ontologies. Based on this declarative representation, we have build OntoMDE, a model-driven engineering toolkit that we have applied to several example ontologies with different Characteristics.
