An Object-Oriented Environment Based On Multi-Layer Application Design

This paper considers both an object-oriented multi-layered approach to application design as well as the programming system which implements the methodology presented. The layered approach was motivated by the need for providing support for di erent kinds of knowledge representation in the application design process and sharing the same object base between software components using these representations. The approach presented is based on layered representation of application using logic for description of application concepts on high level of abstraction and incorporating these into an Object-Oriented (OO) environment. In addition to traditional levels of description in OO systems two original layers are introduced: implicit class description and metaspeci cation. These both are based on logic but of di erent kind. The implicit class description uses Intuitionistic Propositional Calculus and metaspeci cation relies on Horn logic as underlaying fundamental framework. The approach proposed is implemented in the NUT system.