A Formal Proof Environment for uml/ocl

We present the theorem proving environment HOL-OCL that is integrated in a Model-driven Engineering (MDE) framework. HOL-OCL allows to reason over UML class models annotated with OCL specifica- tions. Thus, HOL-OCL strengthens a crucial part of the UML to an object- oriented formal method. HOL-OCL provides several derived proof calculi that allow for formal derivations establishing the validity of UML/OCL formulae. These formulae arise naturally when checking the consistency of class models, when formally refining abstract models to more concrete ones or when discharging side-conditions from model-transformations.