Abstract
OWL has inherent limitations in expressing many Object Oriented (OO) features such as default inheritance, conflict resolution in multiple inheritance, method inheritance and encapsulation. But these features are essential to model real world phenomena, a fact that is underscored by the presence of many object oriented programming languages. OWL chooses not to support these features possibly because of its two design decisions (i) decidability and (ii) low computational complexity. Usually more expressive language tends to be computationally expensive, and in some cases, the language becomes either semi-decidable or undecidable. In this paper, we extend OWL to OWL$++ by supporting two inheritance modes, overriding and inflating, and three inheritance types, value, code and null. Our goal is to increase the expressive power of OWL as well as to maintain it as a computationally efficient decidable language. We demonstrate this by taking translational semantics of OWL++ to OWL. It allows us to build our OWL++ reasoner by using existing technologies such as Jena that works on top of well known OWL reasoners such as Pellet.