Proposal for Improving the UML Abstract Syntax

Different types of consistency of UML models have been described in the literature. The consistency of UML models with the UML static semantics, usually referred as wellformedness, and the consistency between different versions of the same model are among the most cited. The UML models’ well-formedness is a precondition for any other kind of consistency, being described by means of the UML abstract syntax. Unfortunately, this abstract syntax specification is bogus. As a consequence, checking UML models’ consistency is not a natural practice, as it should be. Beginning with 2000, there have been several papers reporting this state of facts, but without any visible consequences on the state of practice. In this paper, the authors propose a new approach (including specification techniques and a process) meant to overcome this specification drawback. Our proposal is based on a long practice of improving the specification of UML Well-Formedness Rules in the OCLE tool.