An Analysis of Aspect Composition Problems

The composition of multiple software units does not always yield the desired results. In particular, aspect-oriented composition mechanisms introduce new kinds of composition problems. These are caused by different characteristics as compared to object-oriented composition, such as inverse dependencies. The aim of this paper is to contribute to the understanding of aspect-oriented composition problems, and eventually composition problems in a more general context. To this extent we propose and illustrate a systematic approach to analyze composition problems in a precise and concrete manner. In this approach we represent aspect-based composition mechanisms as transformation rules on program graphs. We explicitly model and show where composition problems occur, in a way that can easily be fully automated. In this paper we focus on structural superimposition (cf. intertype declarations) to illustrate our approach; this results in the identification of three categories of causes of composition problems. \u

Towards a Tool-based Development Methodology for Pervasive Computing Applications

Despite much progress, developing a pervasive computing application remains a challenge because of a lack of conceptual frameworks and supporting tools. This challenge involves coping with heterogeneous devices, overcoming the intricacies of distributed systems technologies, working out an architecture for the application, encoding it in a program, writing specific code to test the application, and finally deploying it. This paper presents a design language and a tool suite covering the development life-cycle of a pervasive computing application. The design language allows to define a taxonomy of area-specific building-blocks, abstracting over their heterogeneity. This language also includes a layer to define the architecture of an application, following an architectural pattern commonly used in the pervasive computing domain. Our underlying methodology assigns roles to the stakeholders, providing separation of concerns. Our tool suite includes a compiler that takes design artifacts written in our language as input and generates a programming framework that supports the subsequent development stages, namely implementation, testing, and deployment. Our methodology has been applied on a wide spectrum of areas. Based on these experiments, we assess our approach through three criteria: expressiveness, usability, and productivity

Using Transformation-Aspects in Model-Driven Software Product Lines

International audienceModel-Driven Software Product Lines (MD-SPL) are configured by using configuration models and Problem Space metamodels that capture product line scope. Products are derived by means of successive model transformations, starting from problem space models and based on the configuration models. Fine-variations of MD-SPLs correspond to characteristics that afect particular elements of models involved in the model transformations. In this paper, we present an approach to create MD-SPL including fine-variations. We configure products creating fine-feature configurations. Then, based on such configurations, we create MD-SPLs using principles of Aspects Oriented Development. Thus, our approach allows to derive products including fine-grained details of configuration

Towards detecting and solving aspect conflicts and interferences using unit tests

Aspect Oriented Programming (AOP) is a programming paradigm that aims at solving the problem of crosscutting concerns being normally scattered throughout several units of an application.Although an important step forward in the search for modularity, by breaking the notion of encapsulation introduced by Object Oriented Programming (OOP), AOP has proven to be prone to numerous problems caused by conflicts and interferences between aspects.This paper presents work that explores the proven unit testing techniques as a mean to help developers describe the behavior of their aspects and to advise them about possible conflicts and interferences

Disciplined Reuse of Aspects (State of the Art & Work Plan)

This document describes the work plan and state of the art for the PhD work of André Restivo started in 2006. Acceptance of this document by a steering committee is mandatory for the final registration in the Doctoral Programme in Informatics Engineering (ProDEI) at the Engineering Faculty of University of Porto

User-centric product derivation in software product lines

Software Product Line (SPL) engineering aims at achieving efficient development of software products in a specific domain. New products are obtained via a process which entails creating a new configuration specifying the desired product’s features. This configuration must necessarily conform to a variability model, that describes the scope of the SPL, or else it is not viable. To ensure this, configuration tools are used that do not allow invalid configurations to be expressed. A different concern, however, is making sure that a product addresses the stakeholders’ needs as best as possible. The stakeholders may not be experts on the domain, so they may have unrealistic expectations. Also, the scope of the SPL is determined not only by the domain but also by limitations of the development platforms. It is therefore possible that the desired set of features goes beyond what is possible to currently create with the SPL. This means that configuration tools should provide support not only for creating valid products, but also for improving satisfaction of user concerns. We address this goal by providing a user-centric configuration process that offers suggestions during the configuration process, based on the use of soft constraints, and identifying and explaining potential conflicts that may arise. Suggestions help mitigating stakeholder uncertainty and poor domain knowledge, by helping them address well known and desirable domain-related concerns. On the other hand, automated conflict identification and explanation helps the stakeholders to understand the trade-offs required for realizing their vision, allowing informed resolution of conflicts. Additionally, we propose a prototype-based approach to configuration, that addresses the order-dependency issues by allowing the complete (or partial) specification of the features in a single step. A subsequent resolution process will then identify possible repairs, or trade-offs, that may be required for viabilization