JPI Feature Models: Exploring a JPI and FOP Symbiosis for Software Modeling

Looking for a complete modular software development paradigm, this article presents Join Point Interface JPI Feature Models, in the context of a JPI and Feature-Oriented Programming FOP symbiosis paradigm. Therefore, this article describes pros and cons of JPI and FOP approaches for the modular software and software product line production, respective; and highlights the benefits of this mixing proposal; in particular, the JPI Feature Model benefits for a high-level software product line modeling. As an application example, this article applies JPI Features Models on a classic FOP example already modeled using a previous aspect-oriented feature model proposal. Main goals of this application are to visualize traditional feature models preserved components such alternative and optional feature sets and optional and mandatory features as well as special features associations (cross-tree constraints), and differences and advantages with respect to previous research works about extending feature model to support aspect-oriented modeling principles

Proceso marco orientado a aspectos en las etapas tempranas del ciclo de vida del desarrollo de software para una transición en la industria

Por una parte, se halló evidencia de la escasa presencia del paradigma de aspectos en la industria, pero, por otro lado, también se observó que sus beneficios, largamente mencionados en la literatura, sí se pudieron alcanzar en aquellos casos en los que se utilizó la orientación a aspectos en el mundo real, más allá de los ámbitos académicos. Al mismo tiempo, esa evidencia también mostró que las propuestas existentes son incompletas y muy pocas llegan a cubrir tan solo dos fases del ciclo de vida del desarrollo de software (en adelante, SDLC). Por esto es que surgió la motivación de elaborar una alternativa metodológica que permitiera su aplicación de inmediato en proyectos e iniciativas en el mundo real. Así, el objetivo de nuestro trabajo consistió en definir un proceso marco para las etapas tempranas del ciclo de vida del desarrollo de software, desde el modelo de negocios hasta la especificación completa de requisitos de software y empleando el paradigma de la orientación a aspectos. A la vez, se buscó propiciar el empleo en la industria de este paradigma para obtener sus beneficios, al aprovechar las herramientas y técnicas estándares disponibles actualmente en el mercado, mientras se siguen desarrollando otras específicas y alcanzan la madurez suficiente. Por tal razón, se decidió llamar a esta propuesta AOP4ST, sigla derivada de Aspect-Oriented Process for a Smooth Transition. Se trata de un proceso marco, no específico, de modo de permitir su empleo con diferentes modelos del ciclo de vida del desarrollo de software a lo largo de sus etapas tempranas y hasta obtener una especificación de requisitos completa y coherente, incluyendo tres vistas: funcional, estática y de estados. Este proceso emplea herramientas y técnicas estándares, de amplia difusión en la industria, para facilitar su adopción inmediata y, también, utiliza notaciones estándares, para permitir elaborar modelos y especificaciones comprensibles y no ambiguas, que puedan contar con el soporte de las herramientas de software actualmente disponibles en el mercado. Se procura que esta alternativa sea completamente orientada a aspectos, que facilite la obtención de las incumbencias en forma progresiva a lo largo de todos los modelos y, al mismo tiempo, las mantenga siempre separadas y asegurando la trazabilidad bidireccional entre ellas. Estas incumbencias deben obtenerse en forma natural a lo largo de todos los modelos, de manera de no afectar los objetivos propios de cada uno de ellos y, de este modo, potenciar los beneficios que se esperan en cada modelo mediante el empleo del paradigma de aspectos. En la sección 2 se presenta la motivación de este trabajo, incluyendo el estado de la cuestión y la problemática que se pretende resolver, en la sección 3 se describe la solución diseñada para dar solución a los inconvenientes mencionados y los aportes a la disciplina y, finalmente, la sección 4 presenta las líneas de investigación que quedan abiertas a partir de este trabajo.Eje: Tesis de Doctorado.Red de Universidades con Carreras en Informátic

Composing your Compositions of Variability Models

International audienceModeling and managing variability is a key activity in a growing number of software engineering contexts. Support for composing variability models is arising in many engineering scenarios, for instance, when several subsystems or modeling artifacts, each coming with their own variability and possibly developed by different stakeholders, should be combined together. In this paper, we consider the problem of composing feature models (FMs), a widely used formalism for representing and reasoning about a set of variability choices. We show that several composition operators can actually be defined, depending on both matching/merging strategies and semantic properties expected in the composed FM. We present four alternative forms and their implementations. We discuss their relative trade-offs w.r.t. reasoning, customizability, traceability, composability and quality of the resulting feature diagram. We summarize these findings in a reading grid which is validated by revisiting some relevant existing works. Our contribution should assist developers in choosing and implementing the right composition operators

Evolution of component and aspect-based product line architectures

Orientador: Cecília Mary Fischer RubiraTese (doutorado) ¿ Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: Arquiteturas de linhas de produtos são essenciais para facilitar a evolução das linhas, pois ajudam a lidar com sua complexidade, abstraindo seus detalhes de implementação. A variabilidade arquitetural difere arquiteturas de linhas de produtos de arquiteturas de sistemas únicos. Ela reflete a existência de alternativas de projeto arquitetural e é expressa por meio de um conjunto de pontos de variação e variantes arquiteturais. A variabilidade arquitetural pode dificultar a evolução de arquiteturas de linhas produtos, pois a implementação da variabilidade software pode aumentar a complexidade da arquitetura com a possível adição de elementos e dependências extras. A variabilidade de linhas de produtos é usualmente capturada modelo de características e implementado pela arquitetura de linha de produtos. Entretanto, a implementação de características, pontos de variação e variantes podem estar espalhados por diversos elementos arquiteturais, o que dificulta a sua evolução. Em geral, cenários de evolução de linhas de produto envolvem adição e/ou remoção de características, mudança de uma característica obrigatória para opcional, entre outros. Quando cenários de evolução afetam características cujas implementações estão espalhadas na arquitetura, eles podem causar impacto de mudança em vários elementos arquiteturais. Estudos recentes exploram o uso de aspectos para modularizar a implementação de características em arquiteturas de linhas de produtos. Aspectos são usados para modularizar interesses transversais que, no contexto de linhas de produtos, são interesses que afetam diversas características. Contudo, esses estudos não consideram (i) arquiteturas componentizadas com interfaces explícitas e (ii) o uso integrado de componentes e aspectos para modularizar a implementação da variabilidade arquitetural. Idealmente aspectos devem ser modelados o mais cedo possível, de preferência, junto com o modelo de características para possibilitar a criação de arquiteturas bem estruturadas com aspectos. Todavia, não existem modelos que integrem o modelo de características e aspectos, nem métodos que consideram aspectos para gerar arquiteturas de linhas produtos a partir do modelo de características. A solução proposta nesta tese envolve inicialmente um estudo comparativo para mostrar a facilidade de evolução de arquiteturas de linhas de produtos propiciada pelo uso integrado de componentes e aspectos. Em seguida, é proposta uma visão estendida do modelo de características que permite representar características transversais. Essa visão, chamada de visão de características orientada a aspectos, é usada para criar arquiteturas de linhas de produtos orientadas a aspectos. Além disso, um modelo arquitetural de componentes é estendido para integrar aspectos para modularizar a variabilidade arquitetural. Por fim, o método FArM, que provê o mapeamento de modelo de características para modelos de arquitetura de linha de produtos, é estendido para considerar características transversais. Foram conduzidos dois estudos empíricos: um para avaliar se o uso integrado de componentes e aspectos facilita ou não a evolução de arquiteturas de linhas de produtos. O outro estudo empírico avalia a modelagem de características transversais e a extensão do método FArM propostos para projetar arquiteturas de linhas de produtos que sejam fáceis de evoluir. Os dois estudos apresentaram resultados promissores indicando que a solução proposta nesta tese facilita a evolução de arquiteturas de linhas de produtosAbstract: Product line architectures are essential to facilitate the evolution of product lines, as they handle their complexity by abstracting implementation details. Architectural variability is what differs product line architectures from single system architectures. It reflects the existence of alternative design options and it is expressed by a set of architectural variation points and variants. Architectural variability can hinder product line architecture evolution because the implementation of software variability can increase architecture complexity by possibly adding extra elements and dependencies. Product line variability is usually captured in the feature model and it is implemented by product line architectures. However, the implementation of features, variation points, and variants may be scattered over architectural elements, which can hinder its evolution. In general, product line evolution scenarios involve feature addition/removal, changing a mandatory feature to an optional feature, and so forth. When evolution scenarios affect features whose implementations are scattered over architecture, they can cause a great change impact on several architectural elements. Recent studies have explored the use of aspects to modularize feature implementation in product line architectures. Aspects can modularize crosscutting concerns, which, in the context of product lines, are concerns that affect several features. Nevertheless, these studies do not consider (i) componentized architectures with explicit interfaces, and (ii) the integration of aspects and components to modularize the implementation of architectural variability. Ideally, aspects should be modeled as soon as possible, preferably, together with the feature model in order to enable the design of well structured product line architectures with aspects. However, there are neither models which integrate features and aspects, nor methods that considers aspects to design product line architectures from the feature model. The solution proposed in this thesis involves a comparative study that presents the support for product line architecture evolution provided by the integration of components and aspects. Then, it is proposed an extended view of the feature model which enables to represent crosscutting features. This view, called aspect-oriented feature view, is used to design product line architectures with aspects. Lastly, the FArM method, which provides guidelines to map from the feature model to the product line architecture model, is extended to consider crosscutting features. Two empirical studies were conducted: one to assess whether the integration of components and aspects facilitates product line architecture evolution. The other empirical study evaluates whether the crosscutting feature modeling and the FArM method extension proposed supports the design of evolvable product line architectures. Both studies presented promising results which indicate that the solution proposed in this thesis facilitates product line architecture evolutionDoutoradoCiência da ComputaçãoDoutor em Ciência da Computaçã

Feature Model Synthesis

Variability provides the ability to adapt and customize a software system's artifacts for a particular context or circumstance. Variability enables code reuse, but its mechanisms are often tangled within a software artifact or scattered over multiple artifacts. This makes the system harder to maintain for developers, and harder to understand for users that configure the software. Feature models provide a centralized source for describing the variability in a software system. A feature model consists of a hierarchy of features—the common and variable system characteristics—with constraints between features. Constructing a feature model, however, is a arduous and time-consuming manual process. We developed two techniques for feature model synthesis. The first, Feature-Graph-Extraction, is an automated algorithm for extracting a feature graph from a propositional formula in either conjunctive normal form (CNF), or disjunctive normal form (DNF). A feature graph describes all feature diagrams that are complete with respect to the input. We evaluated our algorithms against related synthesis algorithms and found that our CNF variant was significantly faster than the previous comparable technique, and the DNF algorithm performed similarly to a comparable, but newer technique, with the exception of several models where our algorithm was faster. The second, Feature-Tree-Synthesis, is a semi-automated technique for building a feature model given a feature graph. This technique uses both logical constraints and text to address the most challenging part of feature model synthesis—constructing the feature hierarchy—by ranking potential parents of a feature with a textual similarity heuristic. We found that the procedure effectively reduced a modeler's choices from thousands, to five or less when synthesizing the Linux and eCos variability models. Our third contribution is the analysis of Kconfig—a language similar to feature modeling used to specify the variability model of the Linux kernel. While large feature models are reportedly used in industry, these models have not been available to the research community for benchmarking feature model analysis and synthesis techniques. We compare Kconfig to feature modeling, reverse engineer formal semantics, and translate 12 open-source Kconfig models—including the Linux model with over 6000 features—to propositional logic

Modelling, Reverse Engineering, and Learning Software Variability

The society expects software to deliver the right functionality, in a short amount of time and with fewer resources, in every possible circumstance whatever are the hardware, the operating systems, the compilers, or the data fed as input. For fitting such a diversity of needs, it is common that software comes in many variants and is highly configurable through configuration options, runtime parameters, conditional compilation directives, menu preferences, configuration files, plugins, etc. As there is no one-size-fits-all solution, software variability ("the ability of a software system or artifact to be efficiently extended, changed, customized or configured for use in a particular context") has been studied the last two decades and is a discipline of its own. Though highly desirable, software variability also introduces an enormous complexity due to the combinatorial explosion of possible variants. For example, the Linux kernel has 15000+ options and most of them can have 3 values: "yes", "no", or "module". Variability is challenging for maintaining, verifying, and configuring software systems (Web applications, Web browsers, video tools, etc.). It is also a source of opportunities to better understand a domain, create reusable artefacts, deploy performance-wise optimal systems, or find specialized solutions to many kinds of problems. In many scenarios, a model of variability is either beneficial or mandatory to explore, observe, and reason about the space of possible variants. For instance, without a variability model, it is impossible to establish a sampling strategy that would satisfy the constraints among options and meet coverage or testing criteria. I address a central question in this HDR manuscript: How to model software variability? I detail several contributions related to modelling, reverse engineering, and learning software variability. I first contribute to support the persons in charge of manually specifying feature models, the de facto standard for modeling variability. I develop an algebra together with a language for supporting the composition, decomposition, diff, refactoring, and reasoning of feature models. I further establish the syntactic and semantic relationships between feature models and product comparison matrices, a large class of tabular data. I then empirically investigate how these feature models can be used to test in the large configurable systems with different sampling strategies. Along this effort, I report on the attempts and lessons learned when defining the "right" variability language. From a reverse engineering perspective, I contribute to synthesize variability information into models and from various kinds of artefacts. I develop foundations and methods for reverse engineering feature models from satisfiability formulae, product comparison matrices, dependencies files and architectural information, and from Web configurators. I also report on the degree of automation and show that the involvement of developers and domain experts is beneficial to obtain high-quality models. Thirdly, I contribute to learning constraints and non-functional properties (performance) of a variability-intensive system. I describe a systematic process "sampling, measuring, learning" that aims to enforce or augment a variability model, capturing variability knowledge that domain experts can hardly express. I show that supervised, statistical machine learning can be used to synthesize rules or build prediction models in an accurate and interpretable way. This process can even be applied to huge configuration space, such as the Linux kernel one. Despite a wide applicability and observed benefits, I show that each individual line of contributions has limitations. I defend the following answer: a supervised, iterative process (1) based on the combination of reverse engineering, modelling, and learning techniques; (2) capable of integrating multiple variability information (eg expert knowledge, legacy artefacts, dynamic observations). Finally, this work opens different perspectives related to so-called deep software variability, security, smart build of configurations, and (threats to) science

Une modélisation de la variabilité multidimensionnelle pour une évolution incrémentale des lignes de produits

Le doctorat s'inscrit dans le cadre d'une bourse CIFRE et d'un partenariat entre l'ENSTA Bretagne, l'IRISA et Thales Air Systems. Les préoccupations de ce dernier, et plus particulièrement de l'équipe de rattachement, sont de réaliser des systèmes à logiciels prépondérants embarqués. La complexité de ces systèmes et les besoins de compétitivité associés font émerger la notion de "Model-Based Product Lines(MBPLs)". Celles-ci tendent à réaliser une synergie de l'abstraction de l'Ingénierie Dirigée par les Modèles (IDM) et de la capacité de gestion de la capitalisation et réutilisation des Lignes de Produits (LdPs). La nature irrévocablement dynamique des systèmes réels induit une évolution permanente des LdPs afin de répondre aux nouvelles exigences des clients et pour refléter les changements des artefacts internes de la LdP. L'objectif de cette thèse est unique, maîtriser des incréments d'évolution d'une ligne de produits de systèmes complexes, les contributions pour y parvenir sont duales. La thèse est que 1) une variabilité multidimensionnelle ainsi qu'une modélisation relationnelle est requise dans le cadre de lignes de produits de systèmes complexes pour en améliorer la compréhension et en faciliter l'évolution (proposition d'un cadre générique de décomposition de la modélisation et d'un langage (DSML) nommé PLiMoS, dédié à l'expression relationnelle et intentionnelle dans les MBPLs), et que 2) les efforts de spécialisation lors de la dérivation d'un produit ainsi que l'évolution de la LdP doivent être guidé par une architecture conceptuelle (introduction de motifs architecturaux autour de PLiMoS et du patron ABCDE) et capitalisés dans un processus outillé semi-automatisé d'évolution incrémentale des lignes de produits par extension.The PhD (CIFRE fundings) was supported by a partnership between three actors: ENSTA Bretagne, IRISA and Thales Air Systems. The latter's concerns, and more precisely the ones from the affiliation team, are to build embedded software-intensive systems. The complexity of these systems, combined to the need of competitivity, reveal the notion of Model-Based Product Lines (MBPLs). They make a synergy of the capabilities of modeling and product line approaches, and enable more efficient solutions for modularization with the distinction of abstraction levels and separation of concerns. Besides, the dynamic nature of real-world systems induces that product line models need to evolve continually to meet new customer requirements and to reflect changes in product line artifacts. The aim of the thesis is to handle the increments of evolution of complex systems product lines, the contributions to achieve it are twofolds. The thesis claims that i) a multidimensional variability and a relational modeling are required within a complex system product line in order to enhance comprehension and ease the PL evolution (Conceptual model modularization framework and PliMoS Domain Specific Modeling Language proposition; the language is dedicated to relational and intentional expressions in MBPLs), and that ii) specialization efforts during product derivation have to be guided by a conceptual architecture (architectural patterns on top of PLiMoS, e.g.~ABCDE) and capitalized within a semi-automatic tooled process allowing the incremental PL evolution by extension.RENNES1-Bibl. électronique (352382106) / SudocSudocFranceF

XXIII Edición del Workshop de Investigadores en Ciencias de la Computación : Libro de actas

Compilación de las ponencias presentadas en el XXIII Workshop de Investigadores en Ciencias de la Computación (WICC), llevado a cabo en Chilecito (La Rioja) en abril de 2021.Red de Universidades con Carreras en Informátic

Aspect-oriented feature models

Software Product Lines (SPLs) have emerged as a prominent approach for software reuse. SPLs are sets of software systems called families that are usually developed as a whole and share many common features. Feature models are most typically used as a means for capturing commonality and managing variability of the family. A particular product from the family is configured by selecting the desired features of that product. Typically, feature models are considered monolithic entities that do not support modularization well. As industrial feature models tend to be large, their modularization has become an important research topic lately. However, existing modularization approaches do not support modularization of crosscutting concerns. In this paper, we introduce Aspect-oriented Feature Models (AoFM) and argue that using aspect-oriented techniques improves the manageability and reduces the maintainability effort of feature models. Particularly, we advocate an asymmetric approach that allows for the modularization of basic and crosscutting concerns in feature models. \ua9 2011 Springer-Verlag Berlin Heidelberg.Peer reviewed: YesNRC publication: Ye