JOPA: Accessing Ontologies in an Object-oriented Way

Accessing OWL ontologies programmatically by complex IT systems brings many problems stemming from ontology evolution, their open-world nature and expressiveness. This paper presents Java OWL Persistence API (JOPA), a persistence layer that allows using the object-oriented paradigm for accessing semantic web ontologies. Comparing to other approaches, it supports validation of the ontological assumptions on the object level, advanced caching, transactional approach, unification and optimization of repository access through the OntoDriver component, as well as accessing multiple repository contexts at the same time. Additionally, we present a complexity analysis of OntoDriver operations that allows optimizing object-oriented access performance for underlying storage mechanisms. Last but not least, we compare our object-oriented solution to low level Sesame API in terms of efficiency.