Electronic Notes in Theoretical Computer Science URL: www.elsevier.nl/locate/entcs

The meta modeling approach to syntax definition of visual modeling techniques has gained wide acceptance, especially by using it for the definition of UML. Since meta-modeling is non-constructive, it does not provide a systematic way to generate all possible meta model instances. In our approach, an instance-generating graph grammar is automatically created from a given meta model. This graph grammar ensures correct typing and cardinality constraints, but OCL constraints for the meta model are not supported yet. To satisfy also the given OCL constraints, well-formedness checks have to be done in addition. We present a restricted form of OCL constraints that can be translated to graph constraints which can be checked during the instance generation process