Algebraic models of types hierarchy for design and refactoring

Algebraic methods are useful while designing and refactoring object-oriented information systems. Such methods could be used li.e a basis for source code verification and optimization processes. This paper considers.ind of lattice-based algebraic structures that describe object-oriented programming type hierarchy. The article deals with the following properties of these structures: closure, transformation equivalency, existence of logical reduction. Described methodology aims at type hierarchy verification and refactoring. One of the refactoring main goals is the automatic reducing of source code redundancy.