Automated Mapping of UML Activity Diagrams to Formal Specifications for Supporting Containment Checking

Business analysts and domain experts are often sketching the behaviors of a software system using high-level models that are technology- and platform-independent. The developers will refine and enrich these high-level models with technical details. As a consequence, the refined models can deviate from the original models over time, especially when the two kinds of models evolve independently. In this context, we focus on behavior models; that is, we aim to ensure that the refined, low-level behavior models conform to the corresponding high-level behavior models. Based on existing formal verification techniques, we propose containment checking as a means to assess whether the system's behaviors described by the low-level models satisfy what has been specified in the high-level counterparts. One of the major obstacles is how to lessen the burden of creating formal specifications of the behavior models as well as consistency constraints, which is a tedious and error-prone task when done manually. Our approach presented in this paper aims at alleviating the aforementioned challenges by considering the behavior models as verification inputs and devising automated mappings of behavior models onto formal properties and descriptions that can be directly used by model checkers. We discuss various challenges in our approach and show the applicability of our approach in illustrative scenarios.Comment: In Proceedings FESCA 2014, arXiv:1404.043

Ontology-based model abstraction

In recent years, there has been a growth in the use of reference conceptual models to capture information about complex and critical domains. However, as the complexity of domain increases, so does the size and complexity of the models that represent them. Over the years, different techniques for complexity management in large conceptual models have been developed. In particular, several authors have proposed different techniques for model abstraction. In this paper, we leverage on the ontologically well-founded semantics of the modeling language OntoUML to propose a novel approach for model abstraction in conceptual models. We provide a precise definition for a set of Graph-Rewriting rules that can automatically produce much-reduced versions of OntoUML models that concentrate the models’ information content around the ontologically essential types in that domain, i.e., the so-called Kinds. The approach has been implemented using a model-based editor and tested over a repository of OntoUML models

What Do Users Think About Abstractions of Ontology-Driven Conceptual Models?

In a previous paper, we proposed an algorithm for ontology-driven conceptual model abstractions [18]. We have implemented and tested this algorithm over a FAIR Catalog of such models represented in the OntoUML language. This provided evidence for the correctness of the algorithm’s implementation, i.e., that it correctly implements the model transformation rules prescribed by the algorithm, and its effectiveness, i.e., it is able to achieve high compression (summarization) rates over these models. However, in addition to these properties, it is fundamental to test the validity of this algorithm, i.e., that it achieves what it is intended to do, namely provide summarizing abstractions over these models whilst preserving the gist of the conceptualization being represented. We performed three user studies to evaluate the usefulness of the resulting abstractions as perceived by modelers. This paper reports on the findings of these user studies and reflects on how they can be exploited to improve the existing algorithm.</p

Calculating with lenses: optimising bidirectional transformations

This paper presents an equational calculus to reason about bidirectional transformations specified in the point-free style. In particular, it focuses on the so-called lenses as a bidirectional idiom, and shows that many standard laws characterising point-free combinators and recursion patterns are also valid in that setting. A key result is that uniqueness also holds for bidirectional folds and unfolds, thus unleashing the power of fusion as a program optimisation technique. A rewriting system for automatic lens optimisation is also presented, to prove the usefulness of the proposed calculus.(undefined

Developing an Embedded Model for Test suite prioritization process to optimize consistency rules for inconsistencies detection and model changes

Software form typically contains a lot of contradiction and uniformity checkers help engineers find them. Even if engineers are willing to tolerate inconsistencies, they are better off knowing about their existence to avoid follow-on errors and unnecessary rework. However, current approaches do not detect or track inconsistencies fast enough. This paper presents an automated approach for detecting and tracking inconsistencies in real time (while the model changes). Engineers only need to define consistency rules-in any language-and our approach automatically identifies how model changes affect these consistency rules. It does this by observing the behavior of consistency rules to understand how they affect the model. The approach is quick, correct, scalable, fully automated, and easy to use as it does not require any special skills from the engineers using it. We use this model to define generic prioritization criteria that are applicable to GUI, Web applications and Embedded Model. We evolve the model and use it to develop a unified theory. Within the context of this model, we develop and empirically evaluate several prioritization criteria and apply them to four stand-alone GUI and three Web-based applications, their existing test suites and mainly embedded systems. In this model we only run our data collection and test suite prioritization process on seven programs and their existing test suites. An experiment that would be more readily generalized would include multiple programs of different sizes and from different domains. We may conduct additional empirical studies with larger EDS to address this threat each test case has a uniform cost of running (processor time) monitoring (human time); these assumptions may not hold in practice. Second, we assume that each fault contributes uniformly to the overall cost, which again may not hold in practice

Un método para el refinamiento interactivo del diagrama de clases de uml

Durante el proceso de elicitacion de requisitos se presentan problemas de comunicación entre analistas e interesados que suelen ocasionar perdidas de requisitos funcionales. Estas perdidas se aminoran mediante el refinamiento de los esquemas conceptuales, en particular el diagrama de clases de UML. Existen algunos acercamientos al refinamiento del diagrama de clases, pero que no realizan ciclos de interacción con el interesado; otros enfoques realizan refinamiento interactivo del diagrama entidad-relación, un diagrama que no posee toda la información contenida en el diagrama de clases. En este articulo se realiza el refinamiento del diagrama de clases de UML mediante la interacción con el interesado. Para ello, se proponen reglas de completitud que se disparan en lenguaje natural y se emplea un corpus de diagramas de clases para complementar el conocimiento del analista en un determinado dominio. El análisis de completitud propuesto se ilustra con un prototipo en la herramienta UNCDiagramador y se ejemplifica con un caso de estudio

A filtering engine for large conceptual schemas

Postprint (published version

Transformation by example

La transformation de modèles consiste à transformer un modèle source en un modèle cible conformément à des méta-modèles source et cible. Nous distinguons deux types de transformations. La première est exogène où les méta-modèles source et cible représentent des formalismes différents et où tous les éléments du modèle source sont transformés. Quand elle concerne un même formalisme, la transformation est endogène. Ce type de transformation nécessite généralement deux étapes : l’identification des éléments du modèle source à transformer, puis la transformation de ces éléments. Dans le cadre de cette thèse, nous proposons trois principales contributions liées à ces problèmes de transformation. La première contribution est l’automatisation des transformations des modèles. Nous proposons de considérer le problème de transformation comme un problème d'optimisation combinatoire où un modèle cible peut être automatiquement généré à partir d'un nombre réduit d'exemples de transformations. Cette première contribution peut être appliquée aux transformations exogènes ou endogènes (après la détection des éléments à transformer). La deuxième contribution est liée à la transformation endogène où les éléments à transformer du modèle source doivent être détectés. Nous proposons une approche pour la détection des défauts de conception comme étape préalable au refactoring. Cette approche est inspirée du principe de la détection des virus par le système immunitaire humain, appelée sélection négative. L’idée consiste à utiliser de bonnes pratiques d’implémentation pour détecter les parties du code à risque. La troisième contribution vise à tester un mécanisme de transformation en utilisant une fonction oracle pour détecter les erreurs. Nous avons adapté le mécanisme de sélection négative qui consiste à considérer comme une erreur toute déviation entre les traces de transformation à évaluer et une base d’exemples contenant des traces de transformation de bonne qualité. La fonction oracle calcule cette dissimilarité et les erreurs sont ordonnées selon ce score. Les différentes contributions ont été évaluées sur d’importants projets et les résultats obtenus montrent leurs efficacités.Model transformations take as input a source model and generate as output a target model. The source and target models conform to given meta-models. We distinguish between two transformation categories. Exogenous transformations are transformations between models expressed using different languages, and the whole source model is transformed. Endogenous transformations are transformations between models expressed in the same language. For endogenous transformations, two steps are needed: identifying the source model elements to transform and then applying the transformation on them. In this thesis, we propose three principal contributions. The first contribution aims to automate model transformations. The process is seen as an optimization problem where different transformation possibilities are evaluated and, for each possibility, a quality is associated depending on its conformity with a reference set of examples. This first contribution can be applied to exogenous as well as endogenous transformation (after determining the source model elements to transform). The second contribution is related precisely to the detection of elements concerned with endogenous transformations. In this context, we present a new technique for design defect detection. The detection is based on the notion that the more a code deviates from good practice, the more likely it is bad. Taking inspiration from artificial immune systems, we generate a set of detectors that characterize the ways in which a code can diverge from good practices. We then use these detectors to determine how far the code in the assessed systems deviates from normality. The third contribution concerns transformation mechanism testing. The proposed oracle function compares target test cases with a base of examples containing good quality transformation traces, and assigns a risk level based on the dissimilarity between the two. The traces help the tester understand the origin of an error. The three contributions are evaluated with real software projects and the obtained results confirm their efficiencies

Contribution to Quality-driven Evolutionary Software Development process for Service-Oriented Architectures

The quality of software is a key element for the successful of a system. Currently, with the advance of the technology, consumers demand more and better services. Models for the development process have also to be adapted to new requirements. This is particular true in the case of service oriented systems (domain of this thesis), where an unpredictable number of users can access to one or several services. This work proposes an improvement in the models for the software development process based on the theory of the evolutionary software development. The main objective is to maintain and improve the quality of software as long as possible and with the minimum effort and cost. Usually, this process is supported on methods known in the literature as agile software development methods. Other key element in this thesis is the service oriented software architecture. Software architecture plays an important role in the quality of any software system. The Service oriented architecture adds the service flexibility, the services are autonomous and compact assets, and they can be improved and integrated with better facility. The proposed model in this thesis for evolutionary software development makes emphasis in the quality of services. Therefore, some principles of evolutionary development are redefined and new processes are introduced, such as: architecture assessment, architecture recovery and architecture conformance. Every new process will be evaluated with case studies considering quality aspects. They have been selected according to the market demand, they are: the performance, security and evolutionability. Other aspects could be considered of the same way than the three previous, but we believe that these quality attributes are enough to demonstrate the viability of our proposal