Antonio Cicchetti

Automating Co-evolution in Model-Driven Engineering

Software development is witnessing the increasing need of version management techniques for supporting the evolution of model-based artefacts. In this respect, metamodels can be considered one of the basic concepts of model-driven engineering and are expected to evolve during their life-cycle. As a consequence, models conforming to changed metamodels have to be updated for preserving their well-formedness. This paper deals with the co-adaptation problems by proposing higher-order model transformations which take a difference model recording the metamodel evolution and produce a model transformation able to co-evolve the involved models.

A Metamodel Independent Approach to Difference Representation

It is of critical relevance that designers are able to comprehend the various kinds of design-level modifications that a system undergoes throughout its entire lifecycle. In this respect, an interesting and useful operation between subsequent system versions is the model difference calculation and representation. In this paper, a metamodel independent approach to the representation of model differences which is agnostic of the calculation method is presented. Given two models which conform to a metamodel, their difference is conforming to another metamodel derived from the former by an automated transformation. Difference models are first-class entities which induce transformations able to apply the modifications they specify. Finally, difference models can be composed sequentially and in parallel giving place to more complex modifications.

JTL: a bidirectional and change propagating transformation language

In Model Driven Engineering bidirectional transformations are considered a core ingredient for managing both the consistency and synchronization of two or more related models. However, while non-bijectivity in bidirectional transformations is considered relevant, current languages still lack of a common understanding of its semantic implications hampering their applicability in practice. In this paper, the Janus Transformation Language (JTL) is presented, a bidirectional model transformation language specifically designed to support nonbijective transformations and change propagation. In particular, the language propagates changes occurring in a model to one or more related models according to the specified transformation regardless of the transformation direction. Additionally, whenever manual modifications let a model be non reachable anymore by a transformation, the closest model which approximate the ideal source one is inferred. The language semantics is also presented and its expressivity and applicability are validated against a reference benchmark. JTL is embedded in a framework available on the Eclipse platform which aims to facilitate the use of the approach, especially in the definition of model transformations.

Comparison of cross-platform mobile development tools

Mobiles are an integral part of daily life. With time, customers are expecting good and very versatile applications in less time. It is a big challenge to develop high performance mobile applications in this competitive market that would meet the expectation of customers. Mobile operating systems vendors are giving their best available resources for making applications in more convenient ways, although the development of new applications for each mobile operating system in short time is fairly a problem. Cross-platform mobile application development tools contribute in solving this problem largely. This paper presents a pragmatic comparison among four very popular cross platform tools, which are Rhodes, PhoneGap, DragonRad and MoSync. One of the main focuses of the comparison is to provide an overview on the availability of application programming interfaces, programming languages, supported mobile operating systems, licences, and integrated development environments. Furthermore, it also presents some critical points such as the factor of extensibility in tools and the effects that they may bring on market share. The comparison is aimed at supporting developers to make the right choice with respect to their needs/constraints.

Managing Model Conflicts in Distributed Development

The growing complexity of current software systems naturally conveyed their development toward incremental and distributed approaches to speed up the process. Several developers update the same artefact operating concurrent manipulations which need to be coherently combined. The interaction among those changes inevitably involves conflicts which must be detected and reconciled. This paper proposes a domain specific language able to define and manage conflicts caused by cooperative updates over the same model elements. The approach relies on a model-based representation of model differences and enables the specification and the detection of both syntactical and semantic conflicts.

Managing Dependent Changes in Coupled Evolution

In Model-Driven Engineering models and metamodels are not preserved from the evolutionary pressure which inevitably affects almost any artefacts. Moreover, the coupling between models and metamodels implies that when a metamodel undergoes a modification, the conforming models require to be accordingly co-adapted. One of the main obstacles to the complete automation of the adaptation process is represented by the dependencies which occur among the different kinds of modifications. The paper illustrates a dependency analysis, classifies such dependencies, and proposes a metamodeling language driven resolution which is independent from the evolving metamodel and its underlying semantics. The resolution enables a decomposition and consequent scheduling of the adaptation steps allowing the full automation of the process.

Round-trip support for extra-functional property management in model-driven engineering of embedded systems

Context: In order for model-driven engineering to succeed, automated code generation from models through model transformations has to guarantee that extra-functional properties specified at design level are preserved at code level. Objective: The goal of this research work is to provide a full round-trip engineering approach in order to evaluate quality attributes of the embedded system by code execution monitoring as well as code static analysis and then provide back-propagation of the resulting values to modelling level. In this way, properties that can only be roughly estimated statically are evaluated against observed values and this consequently allows to refine the design models for ensuring preservation of analysed extra-functional properties at code level. Method: Following the model-driven engineering vision, (meta-) models and transformations are used as main artefacts for the realisation of the round-trip support which is finally validated against an industrial case study. Result: This article presents an approach to support the whole round-trip process starting from the generation of source code for a target platform, passing through the monitoring of selected system quality attributes at code level, and finishing with the back-propagation of observed values to modelling level. The technique is validated against an industrial case study in the telecommunications applicative domain. Conclusion: Preservation of extra-functional properties through appropriate description, computation and evaluation makes it possible to reduce final product verification and validation effort and costs by generating correct-by-construction code. The proposed round-trip support aids a model-driven component-based development process in ensuring a desired level of extra-functional properties preservation from the source modelling artefacts to the generated code.

CHESS: a model-driven engineering tool environment for aiding the development of complex industrial systems

Modern software systems require advanced design support especially capable of mastering rising complexity, as well as of automating as many development tasks as possible. Model-Driven Engineering (MDE) is earning consideration as a solid response to those challenges on account of its support for abstraction and domain specialisation. However, MDE adoption often shatters industrial practice because its novelty opposes the need to preserve vast legacy and to not disband the skills matured in pre-MDE or alternative development solutions. This work presents the CHESS tool environment, a novel approach for cross-domain modelling of industrial complex systems. It leverages on UML profiling and separation of concerns realised through the specification of well-defined design views, each of which addresses a particular aspect of the problem. In this way, extra-functional, functional, and deployment descriptions of the system can be given in a focused manner, avoiding issues pertaining to distinct concerns to interfere with one another.

Design of adaptive security mechanisms for real-time embedded systems

Introducing security features in a system is not free and brings along its costs and impacts. Considering this fact is essential in the design of real-time embedded systems which have limited resources. To ensure correct design of these systems, it is important to also take into account impacts of security features on other non-functional requirements, such as performance and energy consumption. Therefore, it is necessary to perform trade-off analysis among non-functional requirements to establish balance among them. In this paper, we target the timing requirements of real-time embedded systems, and introduce an approach for choosing appropriate encryption algorithms at runtime, to achieve satisfaction of timing requirements in an adaptive way, by monitoring and keeping a log of their behaviors. The approach enables the system to adopt a less or more time consuming (but presumably stronger) encryption algorithm, based on the feedback on previous executions of encryption processes. This is particularly important for systems with high degree of complexity which are hard to analyze statistically.

Supporting incremental synchronization in hybrid multi-view modelling

Multi-view modelling is a widely accepted technique to reduce the complexity in the development of modern software systems. It allows developers to focus on a narrowed portion of the specification dealing with a selected aspect of the problem. However, multi-view modelling support discloses a number of issues mainly due to consistency management, expressiveness, and customization needs. A possible solution to alleviate those problems is to adopt a hybrid solution for multi-view modelling based on an arbitrary number of custom views defined on top of an underlying modelling language. In this way it is possible to benefit from the consistency by-construction granted by well-formed views while at the same time providing malleable perspectives through which the system under development can be specified. In this respect, this paper presents an approach for supporting synchronization mechanism based on model differences in hybrid multi-view modelling. Model differences allow to focus only on the manipulations operated by the user in a particular view, and to propagate them to the other views in a incremental way thus reducing the overhead of a complete recomputation of modified models.