Fiona Polack

The Epsilon Transformation Language

Support for automated model transformation is essential for realizing a Model Driven Development (MDD) process. However, model transformation is only one of the many tools in a model engineering toolkit. To apply MDD in the large, automated support for a number of additional tasks such as model comparison, merging, validation and model-to-text transformation, is essential. While a number of successful model transformation languages have been currently proposed, the majority of them have been developed in isolation and as a result, they face consistency and integration difficulties with languages that support other model management tasks. We present the Epsilon Transformation Language (ETL), a hybrid model transformation language that has been developed atop the infrastructure provided by the Epsilon model management platform. By building atop Epsilon, ETL is seamlessly integrated with a number of other task-specific languages to help to realize composite model management workflows.

The epsilon object language (EOL)

Model-Driven Development requires model management languages and tools for supporting model operations such as editing, consistency checking, and transformation. At the core of these model management techniques is a set of facilities for model navigation and modification. A subset of the Object Constraint Language can be used for some of these tasks, but it has limitations as a general-purpose language to be used in a variety of model management tasks. We present the metamodel independent Epsilon Object Language (EOL) which builds on OCL. EOL can be used both as a standalone generic model management language or as infrastructure on which task-specific languages can be built. We describe how it has been used to construct a selection of languages, such as model merging, comparison, and text generation languages.

Model migration with epsilon flock

In their recent book, Mens and Demeyer state that Model-Driven Engineering introduces additional challenges for controlling and managing software evolution. Today, tools exist for generating model editors and for managing models with transformation, validation, merging and weaving. There is limited support, however, for model migration - a development activity in which instance models are updated in response to metamodel evolution. In this paper, we describe Epsilon Flock, a model-to-model transformation language tailored for model migration that contributes a novel algorithm for relating source and target model elements. To demonstrate its conciseness, we compare Flock to other approaches.

Model comparison: a foundation for model composition and model transformation testing

In the context of Model Driven Development, Model Transformation and Model Composition are two essential model management tasks. In this paper, we demonstrate how both tasks can benefit, in different ways, from the automation of another fundamental task: Model Comparison. We derive requirements for a model comparison solution incrementally, and demonstrate a concrete rule-based model comparison approach we have developed in the context of a generic model merging language.

The Epsilon Generation Language

We present the Epsilon Generation Language (EGL), a model-to-text (M2T) transformation language that is a component in a model management tool chain. The distinctive features of EGL are described, in particular its novel design which inherits a number of language concepts and logical features from a base model navigation and modification language. The value of being able to use a M2T language as part of an extensible model management tool chain is outlined in a case study, and EGL is compared to other M2T languages.

On the evolution of OCL for capturing structural constraints in modelling languages

The Object Constraint Language (OCL) can be used to capture structural constraints in the context of the abstract syntax of modelling languages (metamodels) defined in the MOF metamodelling architecture. While the expression language of OCL has been revised and updated a number of times since its inception, the constructs used for capturing constraints (invariants) have remained unchanged. In this paper we argue that the abstract and concrete syntax of OCL invariants should also be updated to address a number of shortcomings and render OCL more usable in a contemporary modelling environment. To support our arguments we have implemented the proposed extensions in the prototype Epsilon Validation Language (EVL). To demonstrate the benefits delivered, we present and discuss a concrete example.

Taming EMF and GMF using model transformation

EMF and GMF are powerful frameworks for implementing tool support for modelling languages in Eclipse. However, with power comes complexity; implementing a graphical editor for a modelling language using EMF and GMF requires developers to hand craft and maintain several low-level interconnected models through a loosely-guided, labour-intensive and error-prone process. In this paper we demonstrate how the application of model transformation techniques can help with taming the complexity of GMF and EMF and deliver significant productivity, quality, and maintainability benefits. We also present EuGENia, an open-source tool that implements the proposed approach, illustrate its functionality through an example, and report on the communitys response to the tool.

The Design of a Conceptual Framework and Technical Infrastructure for Model Management Language Engineering

Model management is the discipline of managing artefacts used in Model-Driven Engineering (MDE). A model management framework defines and implements the operations (such as transformation or code generation) required to manipulate MDE artefacts. Modern approaches to model management generally implement these operations via domain-specific languages (DSLs). This paper presents and compares the principles behind three approaches to implementing DSLs for model management and identifies some of the key differences between DSL engineering in general and for model management. It then shows how theory relates to practice by illustrating how DSL design and implementation approaches have been used in practice to build working languages from the Epsilon model management framework. A set of questions for guiding the development of new model management DSLs is summarised, and data on development costs for the different approaches is presented.

A comparison of model migration tools

Modelling languages and thus their metamodels are subject to change. When a metamodel evolves, existing models may no longer conform to the evolved metamodel. To avoid rebuilding them from scratch, existing models must be migrated to conform to the evolved metamodel. Manually migrating existing models is tedious and errorprone. To alleviate this, several tools have been proposed to build a migration strategy that automates the migration of existing models. Little is known about the advantages and disadvantages of the tools in different situations. In this paper, we thus compare a representative sample of migration tools - AML, COPE, Ecore2Ecore and Epsilon Flock - using common migration examples. The criteria used in the comparison aim to support users in selecting the most appropriate tool for their situation.

Update Transformations in the Small with the Epsilon Wizard Language

We present the Epsilon Wizard Language (EWL), a tool-supported language for specifying and executing automated update transformations in the small based on existing model elements and input from the user. We discuss on EWL’s requirements and relevant design decisions, as well as the infrastructure upon which the language has been developed. We also provide concrete working examples to demonstrate how EWL can be used to automate the process of constructing and refactoring models.