Generating Counterexamples of Model-based Software Product Lines: An Exploratory Study

International audienceModel-based Software Product Line (MSPL) engineering ai- ms at deriving customized models corresponding to individ- ual products of a family. MSPL approaches usually promote the joint use of a variability model, a base model expressed in a specific formalism, and a realization layer that maps variation points to model elements. The design space of an MSPL is extremely complex to manage for the engineer, since the number of variants may be exponential and the derived product models have to be conformant to numerous well-formedness and business rules. In this paper, the objec- tive is to provide a way to generate MSPLs, called counterex- amples, that can produce invalid product models despite a valid configuration in the variability model. We provide a systematic and automated process, based on the Common Variability Language (CVL), to randomly search the space of MSPLs for a specific formalism. We validate the effective- ness of this process for three formalisms at different scales (up to 247 metaclasses and 684 rules). We also explore and discuss how counterexamples could guide practitioners when customizing derivation engines, when implementing check- ing rules that prevent early incorrect CVL models, or simply when specifying an MSPL

Automated Verification of Care Pathways Using Constraint Programming

Bad construction of modeled care pathways can lead to satisfiability problems during the pathway execution. These problems can ultimately result in medical errors and need to be checked as formally as possible. Therefore, this study proposes a set of algorithms using a free open-source library dedicated to constraint programming allied with a DSL to encode and verify care pathways, checking four possible problems: states in deadlock, non-determinism, inaccessible steps and transitions with logically equivalent guard conditions. We then test our algorithms in 84 real care pathways used both in hospitals and surgeries. Using our algorithms, we were able to find 200 problems taking less than 1 second to complete the verification on most pathways

Generating Counterexamples of Model-based Software Product Lines: An Exploratory Study

International audienceModel-based Software Product Line (MSPL) engineering ai- ms at deriving customized models corresponding to individ- ual products of a family. MSPL approaches usually promote the joint use of a variability model, a base model expressed in a specific formalism, and a realization layer that maps variation points to model elements. The design space of an MSPL is extremely complex to manage for the engineer, since the number of variants may be exponential and the derived product models have to be conformant to numerous well-formedness and business rules. In this paper, the objec- tive is to provide a way to generate MSPLs, called counterex- amples, that can produce invalid product models despite a valid configuration in the variability model. We provide a systematic and automated process, based on the Common Variability Language (CVL), to randomly search the space of MSPLs for a specific formalism. We validate the effective- ness of this process for three formalisms at different scales (up to 247 metaclasses and 684 rules). We also explore and discuss how counterexamples could guide practitioners when customizing derivation engines, when implementing check- ing rules that prevent early incorrect CVL models, or simply when specifying an MSPL

Interactive Visualisation of Products in Online Configurators: A Case Study for Variability Modelling Technologies

International audienceNumerous companies develop interactive environments to assist users in customising sales products through the selection of con- figuration options. A visual representation of these products is an important factor in terms of user experience. However, an analysis of 100+ existing configurators highlights that not all provide visual representations of configured products. One of the current challenges is the trade-off developers face between either the memory consuming use of pregenerated images of all the combinations of options, or rendering products on the fly, which is non trivial to implement efficiently. We believe that a new approach to associate product configurations to visual representations is needed to compose and render them dynamically. In this paper we present a formal statement of the problem and a model-driven perspective for addressing it as well as our ongoing work and further challenges

Generating Counterexamples of Model-based Software Product Lines

International audienceIn a Model-based Software Product Line (MSPL), the variability of the domain is characterized in a variability model and the core artifacts are base models conforming to a modeling language (also called metamodel). A realization model connects the features of the variability model to the base model elements, triggering operations over these elements based on a configuration. The design space of an MSPL is extremely complex to manage for the engineer, since the number of variants may be exponential and the derived product models have to be conforming to numerous well-formedness and business rules. In this paper, the objective is to provide a way to generate MSPLs, called counterexamples (also called anti-patterns), that can produce invalid product models despite a valid configuration in the variability model. We describe the foundations and motivate the usefulness of counterexamples (e.g., inference of guidelines or domain-specific rules to avoid earlier the specification of incorrect mappings; testing oracles for increasing the robustness of derivation engines given a modeling language). We provide a generic process, based on the Common Variability Language (CVL) to randomly search the space of MSPLs for a specific modelling language. We develop LineGen a tool on top of CVL and modeling technologies to support the methodology and the process. LineGen targets different scenarios and is flexible to work either with just a domain metamodel as input or also with pre-defined variability models and base models. We validate the effectiveness of this process for three formalisms at different scales (up to 247 metaclasses and 684 rules). We also apply the approach in the context of a real industrial scenario involving a large-scale metamodel

MatrixMiner: A Red Pill to Architect Informal Product Descriptions in the Matrix

International audienceDomain analysts, product managers, or customers aim to capture the important features and differences among a set of related products. A case-by-case reviewing of each product description is a laborious and time-consuming task that fails to deliver a condensed view of a product line. This paper introduces MatrixMiner: a tool for automatically synthesizing product comparison matrices (PCMs) from a set of product descriptions written in natural language. Ma-trixMiner is capable of identifying and organizing features and values in a PCM – despite the informality and absence of structure in the textual descriptions of products. Our empirical results of products mined from BestBuy show that the synthesized PCMs exhibit numerous quantitative, comparable information. Users can exploit MatrixMiner to visualize the matrix through a Web editor and review, refine, or complement the cell values thanks to the traceability with the original product descriptions and technical specifications

Tooling Support for Variability and Architectural Patterns in Systems Engineering

International audienceIn systems engineering, the deployment of software components is error-prone since numerous safety and security rules have to be preserved. Furthermore, many deployments on different heterogeneous platforms are possible. In this paper we present a technological solution to assist industrial practitioners in producing a safe and secure solution out of numerous architectural variants. First, we introduce a pattern technology that provides correct-by-construction deployment models through the reuse of modeling artifacts organized in a catalog. Second, we develop a variability solution , connected to the pattern technology and based on an extension of the common variability language, for supporting the synthesis of model-based architectural variants. This paper describes a live demonstration of an industrial effort seeking to bridge the gap between variability modeling and model-based systems engineering practices. We illustrate the tooling support with an industrial case study (a secure radio platform)