1. Future Work  Formal specification of modeling language semantic is key issue  Reliance on well-established formal models of computation (i.e. finite state machines, data flow, discrete event systems)  Such an approach: Semantic Anchoring  Usage of canonical, executable models of computation (MoC)  Usage of graph transformation algorithms for mapping

2. Institute for Software Integrated Systems Vanderbilt University Metamodel Composition Matthew Emerson and Janos Sztipanovits Presented by: Zoltán Molnár

3. State of the art  Metamodeling more of an art than science  Built from scratch  No public collection of reusable metamodels  Few best-practices for metamodeling (not understood or documented)  Benefits of metamodel libraries:  Avoidance of duplication  Emergence of high quality metamodel fragments  Recognition of key patterns and best-practices  Reduction in time-to-market for new DSMLs

4. Metamodel Merge  MOF: Package Merge  Recursive unioning of model elements  No relation with the originating packages  MetaGME: Class Equivalence and Inheritance  Implementation and interface inheritance

5. Metamodel Interfacing  Conceptually different but related domains  Explore interactions between two domains  Delineation of an interface  consists of new modeling elements  relations

6. Class Refinement  A concept captured by:  DSML A in detail  DSML B as black-box  Relation between the constructs is hierarchical +

7. Template Instantiation  Intended for reuse of common patterns  Common patterns recorded as abstract templates  Instantiate (replicate & concretize)  Templates:  Composition hierarchies  Modular interconnections  StateCharts-style  Data Flow graphs  Proxy metamodeling pattern

8. New relations New elements Composition with merge (inheritance)

9. Template Instantiation Tool  User initiates a template inclusion  Selected abstract metamodel fragment looked up  Existing objects in the metamodel are selected for roles in the chosen template (some roles might be left unbound)  Metamodel updated with the template  New relations established  New objects created for unbound roles

10. New relationsNew elements Composition with template applied twice

11. Vision  Unified Tool  Template Instantiation integrated with MIC toolset  GReAT  Benefits of composition  Semantics  Semantic mappings  Property preserving model transformations