Real Models are Really on M0 - Or How to Make Programmers Use Modeling Joachim Fischer1 a, Birger Møller-Pedersen2 b and Andreas Prinz3 c 1Department of Computer Science, Humboldt University, Berlin, Germany 2Department of Informatics, University of Oslo, Oslo, Norway 3Department of ICT, University of Agder, Grimstad, Norway fi
[email protected], birger@ifi.uio.no,
[email protected] Keywords: Model, System, Language, Ontological Modeling. Abstract: This paper discusses the term ’model’ and the role of the level M0 in the four-layer metamodeling architecture of MOF/OMG. It illustrates the failures of the OMG MOF standard and how a model is an abstraction, not a description. We apply two simple approaches: (1) observing the use of models (of real or planned systems) in system development, including prototyping, simulations, and models in general, and (2) comparing modeling with programming. These approaches lead to the conclusion that models should be placed on M0, while UML models are model descriptions. This conclusion leads to a better understanding of InstanceSpecification for description of snapshots, and of metamodeling applied to ontologies. 1 INTRODUCTION standing by looking at the use of models in systems development, thereby giving the right role to models. Modeling and programming communities are diverg- The ultimate goal of systems development is to ing, each developing their own languages and tools1. produce systems, i.e. changing sets of executing ob- Programmers mainly focus on (program) execu- jects that interact with each other and with entities in tions, while modellers handle different kinds of what the environment of the systems. Systems are made in the modeling community are called models (do- using various kinds of descriptions, ultimately pro- main models, requirements and design models) in a grams from which executions with objects (on level mixture of diagrams and text.