Abstract (eng)
It has been recognised that model-based engineering (MBE) approaches are beneficial for the engineering of increasingly complex systems and software. MBE encourages the usage of modelling languages and methods to analyse, design and develop various kinds of enterprise and software systems. A multitude of standard and domain-specific modelling languages (DSML) are being engineered to facilitate modelling. While focusing on a narrow domain, DSMLs are composed into hybrid modelling languages, to benefit from their combined use, i.e. to address the system complexity from different perspectives holistically. Furthermore, modelling languages in general evolve over time, requiring adaptations, extensions and customisation to accommodate the changing requirements of a problem domain. Language definition is a complex engineering task. Metamodelling has been recognised as a practical yet rigorous formalism for language definition with a metamodel being its pivotal engineering artefact. While current metamodelling techniques provide powerful concepts for creating metamodels from scratch, they lack concepts for more efficient metamodelling. To answer the challenges posed by an increasing need for new modelling languages in general and by their hybrid and evolving nature in particular, this thesis introduces an approach to modular metamodel engineering (MME). Based on the hypothesis that modularisation and composition reduce effort and improve efficiency in metamodel definition, the thesis extends existing metamodelling concepts towards modular definition of metamodels. In particular, the thesis introduces concepts for defining reusable metamodel fragments and a comprehensive set of metamodel composition operators for fragment combination. By promoting reuse, such a modular approach allows for systematic, flexible and efficient definition and customisation of metamodels. The introduced concepts are formalised in a language for modular metamodel engineering (MMEL). A possible realisation of MMEL is explicated based on the ADOxx metamodelling platform. Finally, the MME approach and in particular the language MMEL is evaluated in two case studies of enterprise modelling methods in the context of OMILab. On the one side, MMEL is applied to modularise the hybrid modelling method BPMS. On the other side, MMEL is used to design a hybrid DSML that combines a language for network devices modelling with the ontology language OWL.