Formalization of the UML Metamodel: An Approach Based Upon the Four-Layer Metamodeling Architecture

Modeling tools move towards more and more abstract approaches such as metamodels and the four-layer metamodeling architecture. We address modeling tools using the UML metamodel as a core. We propose a fourlayer metamodeling architecture based upon a two-fold structure of metametamodel and metamodel layers. The meta-metamodel layer is populated with a lattice of modeling paradigms that are instantiated –at metamodel level– as specializations of the UML metamodel. The inheritance hierarchy of metamodels is a mirror of the lattice of modeling paradigms. Different pre-conditions may be used to guard the instantiation of ambiguous modeling paradigms. Non-strict pre-conditions allow a “delayed formalization” of the UML metamodel.