Enhanced Graph Rewriting Systems for Complex Software Domains (SoSyM Abstract)

International audienceMethodologies for correct by construction reconfigu-rations can efficiently solve consistency issues in dynamic software architecture. Graph-based models are appropriate for designing such architectures and methods. At the same time, they may be unfit to characterize a system from a non functional perspective. This stems from efficiency and applicability limitations in handling time-varying characteristics and their related dependencies. In order to lift these restrictions, an extension to graph rewriting systems is proposed herein. The suitability of this approach, as well as the restraints of currently available ones, are illustrated, analysed and experimentally evaluated with reference to a concrete example. This investigation demonstrates that the conceived solution can: (i) express any kind of algebraic dependencies between evolving requirements and properties; (ii) significantly ameliorate the efficiency and scalability of system modifications with respect to classic methodologies; (iii) provide an efficient access to attribute values; (iv) be fruitfully exploited in software management systems; (v) guarantee theoretical properties of a grammar, like its termination. This is an extended abstract for the Models 2015 Conference of the journal paper of the same name [1]. I. MOTIVATION Dynamic software architectures enable adaptation in evolving distributed systems. A crucial undesirable implication of such adaptations is a potential loss of correctness, the system withdrawing from its scope of consistency. Besides correctness, the system has evolving non-functional requirements, which are tightly linked to its appropriateness or efficiency. The satisfaction of these objectives depends on the properties of the system, its components, and their relations. On one hand, graph-based models are appropriate for the design of adaptation rules that necessarily preserve the system's consistency. On the other, currently available graph based methods exhibit limitations with regard to the description of system properties, in particular regarding their evolution and inter-dependencies

Model-Driven Engineering and Optimizing Compilers: A bridge too far?

International audienceA primary goal of Model Driven Engineering (MDE) is to reduce the cost and effort of developing complex software systems using techniques for transforming abstract views of software to concrete implementations. The rich set of tools that have been developed, especially the growing maturity of model transformation technologies, opens the possibility of applying MDE technologies to transformation-based problems in other domains. In this paper, we present our experience with using MDE technologies to build and evolve compiler infrastructures in the optimizing compiler domain.We illustrate, through our two ongoing research compiler projects for C and a functional language, the challenging aspects of optimizing compiler research and show how mature MDE technologies can be used to address them.We also identify some of the pitfalls that arise from unrealistic expectations of what can be accomplished using MDE and discuss how they can lead to unsuccessful and frustrating application of MDE technologies

Semantics of OCL specified with QVT

The Object Constraint Language (OCL) has been for many years formalized both in its syntax and semantics in the language standard. While the official definition of OCL's syntax is already widely accepted and strictly supported by most OCL tools, there is no such agreement on OCL's semantics, yet. In this paper, we propose an approach based on metamodeling and model transformations for formalizing the semantics of OCL. Similarly to OCL's official semantics, our semantics formalizes the semantic domain of OCL, i.e. the possible values to which OCL expressions can evaluate, by a metamodel. Contrary to OCL's official semantics, the evaluation of OCL expressions is formalized in our approach by model transformations written in QVT. Thanks to the chosen format, our semantics definition for OCL can be automatically transformed into a tool, which evaluates OCL expressions in a given context. Our work on the formalization of OCL's semantics resulted also in the identification and better understanding of important semantic concepts, on which OCL relies. These insights are of great help when OCL has to be tailored as a constraint language of a given DSL. We show on an example, how the semantics of OCL has to be redefined in order to become a constraint language in a database domai

Backwards reasoning for model transformations: Method and applications

This is the author’s version of a work that was accepted for publication in Journal of Systems and Software. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Systems and Software, VOL 116, (2016) DOI 10.1016/j.jss.2015.08.017Model transformations are key elements of Model Driven Engineering. Current challenges for transformation languages include improving usability (i.e., succinct means to express the transformation intent) and devising powerful analysis methods. In this paper, we show how backwards reasoning helps in both respects. The reasoning is based on a method that, given an OCL expression and a transformation rule, calculates a constraint that is satisfiable before the rule application if and only if the original OCL expression is satisfiable afterwards. With this method we can improve the usability of the rule execution process by automatically deriving suitable application conditions for a rule (or rule sequence) to guarantee that applying that rule does not break any integrity constraint (e.g. meta-model constraints). When combined with model finders, this method facilitates the validation, verification, testing and diagnosis of transformations, and we show several applications for both inplace and exogenous transformations.Work partially funded by the Spanish Ministry of Economy and Competitiveness (projects TIN2008-00444, TIN2011-24139 and TIN2014-52129-R), the Community of Madrid with project SICOMORO (S2013/ICE-3006), the EU Commission with project MONDO (FP7-ICT-2013-10, #611125) and a research grant from UOC-IN3 (Internet Interdisciplinary Institute). We would like to thank Hamza Ed-Douibi for his work on the tool implementation part, and the reviewers for their useful comments

Model Transformation Languages with Modular Information Hiding

Model transformations, together with models, form the principal artifacts in model-driven software development. Industrial practitioners report that transformations on larger models quickly get sufficiently large and complex themselves. To alleviate entailed maintenance efforts, this thesis presents a modularity concept with explicit interfaces, complemented by software visualization and clustering techniques. All three approaches are tailored to the specific needs of the transformation domain

Model Transformation Languages with Modular Information Hiding

Model transformations, together with models, form the principal artifacts in model-driven software development. Industrial practitioners report that transformations on larger models quickly get sufficiently large and complex themselves. To alleviate entailed maintenance efforts, this thesis presents a modularity concept with explicit interfaces, complemented by software visualization and clustering techniques. All three approaches are tailored to the specific needs of the transformation domain

Towards Language-Oriented Modeling

In this habilitation à diriger des recherches (HDR), I review a decade of research work in the fields of Model-Driven Engineering (MDE) and Software Language Engineering (SLE). I propose contributions to support a language-oriented modeling, with the particular focus on enabling early validation & verification (V&V) of software-intensive systems. I first present foundational concepts and engineering facilities which help to capture the core domain knowledge into the various heterogeneous concerns of DSMLs (aka. metamodeling in the small), with a particular focus on executable DSMLs to automate the development of dynamic V&V tools. Then, I propose structural and behavioral DSML interfaces, and associated composition operators to reuse and integrate multiple DSMLs (aka. metamodeling in the large).In these research activities I explore various breakthroughs in terms of modularity and reusability of DSMLs. I also propose an original approach which bridges the gap between the concurrency theory and the algorithm theory, to integrate a formal concurrency model into the execution semantics of DSMLs. All the contributions have been implemented in software platforms — the language workbench Melange and the GEMOC studio – and experienced in real-world case studies to assess their validity. In this context, I also founded the GEMOC initiative, an attempt to federate the community on the grand challenge of the globalization of modeling languages

Model Transformation Testing and Debugging: A Survey

Model transformations are the key technique in Model-Driven Engineering (MDE) to manipulate and construct models. As a consequence, the correctness of software systems built with MDE approaches relies mainly on the correctness of model transformations, and thus, detecting and locating bugs in model transformations have been popular research topics in recent years. This surge of work has led to a vast literature on model transformation testing and debugging, which makes it challenging to gain a comprehensive view of the current state of the art. This is an obstacle for newcomers to this topic and MDE practitioners to apply these approaches. This paper presents a survey on testing and debugging model transformations based on the analysis of \nPapers~papers on the topics. We explore the trends, advances, and evolution over the years, bringing together previously disparate streams of work and providing a comprehensive view of these thriving areas. In addition, we present a conceptual framework to understand and categorise the different proposals. Finally, we identify several open research challenges and propose specific action points for the model transformation community.This work is partially supported by the European Commission (FEDER) and Junta de Andalucia under projects APOLO (US-1264651) and EKIPMENT-PLUS (P18-FR-2895), by the Spanish Government (FEDER/Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación) under projects HORATIO (RTI2018-101204-B-C21), COSCA (PGC2018-094905-B-I00) and LOCOSS (PID2020-114615RB-I00), by the Austrian Science Fund (P 28519-N31, P 30525-N31), and by the Austrian Federal Ministry for Digital and Economic Affairs and the National Foundation for Research, Technology and Development (CDG