Octavian Patrascoiu

A relational approach to defining and implementing transformations between metamodels

The Model-Driven Architecture initiative of the OMG promotes the idea of transformations in the context of mapping from platform independent to platform specific models. Additionally, the popularity of XML and the wide spread use of XSLT has raised the profile of model transformation as an important technique for computing. In fact, computing may well be moving to a new paradigm in which models are considered first class entities and transformations between them are a major function performed on those models. This paper proposes an approach to defining and implementing model transformations which uses metamodelling patterns to capture the essence of mathematical relations. It shows how these patterns can be used to define the relationship between two different metamodels. A goal of the approach is to enable complete specifications from which tools can be generated. The paper describes implementations of the examples, which have been partially generated from the definitions using a tool generation tool. A number of issues emerge which need to be solved in order to achieve the stated goal; these are discussed.

Mapping EDOC to Web services using YATL

Modeling is a technique used extensively in industry to define software systems, the UML being the most prominent example. With the increased use of modeling techniques has come the desire to use model transformations. The current paper presents the mapping from EDOC profiles to Web services using a transformation language called YATL (yet another transformation language). This transformation language has been defined to perform transformations within the OMGs model driven architecture (MDA) framework. After having presented YATL, we present an experiment to show how YATL can be used to map from EDOC to Web services. YATL is still evolving since it is supposed to match the forthcoming OMGs query/views/transformations (QVT) standard.

OCL 2.0 - Implementing the Standard for Multiple Metamodels

OCL 2.0 is the newest version of the OMG’s constraint language to accompany their suit of Object Oriented modelling languages. The use of OCL as an accompanying constraint and query language to modelling with these languages is essential. As tools are built to support the modelling languages, it is also necessary to implement the OCL. This paper reports our experience of implementing OCL based on the latest version of the OMG’s OCL standard. We provide an ecient LALR grammar for parsing the language and describe an architecture that enables the language to be bridged to any OO modelling language. In addition we give feedback on problems and ambiguities discovered in the standard, with some suggested solutions.

Tool support for OCL and related formalisms – needs and trends

The recent trend in software engineering to model-centered methodologies is an excellent opportunity for OCL to become a widely used specification language. If the focus of the development activities is shifted from implementation code to more abstract models then software developers need a formalism to provide a complete, unambiguous and consistent model at a very detailed level. OCL is currently the only language that can bring this level of detail to UML models. The purpose of the workshop was to identify future challenges for OCL and to discuss how OCL and its current tool support can be improved to meet these challenges. The workshop gathered numerous experts from academia and industry to report on success stories, to formulate wishes to the next generation of OCL tools, and to identify weaknesses in the language, which make OCL sometimes cumbersome to use. The workshop could also attract numerous people whose aim was to get an overview on the state of the art of OCL tool support and on how OCL can efficiently be applied in practice.

OCL and model driven engineering

Precise modeling is essential to the success of the OMG’s Model Driven Architecture initiative. At the modeling level (M1) OCL allows for the precision needed to write executable models. Can OCL be extended to become a full high-level executable language with side-effects? At the meta-level (M2), queries, views and transformations are subjects that will be vital to the success of the OMG’s Model Driven Architecture initiative. Will OCL 2.0 become an essential part of the Queries/Views/Transformations standard and what will be its application areas in industry? Can the features of OCL 2.0 be used in the Model Driven Engineering (MDE) approach? This workshop aims at bringing together people from academia that are expected to report on inspiring ideas for innovative application scenarios and tools, and industrial practitioners, which are expected to provide statements on their view of the future of OCL in the context of MDE.