Tewfik Ziadi

Towards a UML profile for software product lines

This paper proposes a UML profile for software product lines. This profile includes stereotypes, tagged values, and structural constraints and it makes possible to define PL models with variabilities. Product derivation consists in generating product models from PL models. The derivation should preserve and ensure a set of constraints which are specified using the OCL.

Software Product Line Engineering with the UML: Deriving Products

Abstract Software product line engineering introduces two new dimensions into the traditional engineering of software-based systems: the variability modeling and the product derivation. The variability gathers characteristics that differ from one product to another, while the product derivation is defined as a complete process of building products from the product line. Software Product Line Engineering with the UML has received a lot of attention in recent years. However most of these works only concern variability modeling in UML static models and few works concern behavioral models . In addition, there is very little research on product derivation. This chapter investigates the product derivation in the context of the product line engineering with the UML. First, a set of extensions are proposed to model product line variability in two types of UML mo dels: class diagrams (t he static aspect) and sequence diagrams (the behavioral aspect). Then we formalize product derivation using a UML model transformation. An algorithm is give n to derive a static model for a product and an algebraic approach is proposed to derive product-specific statecharts from the sequence diagrams of the product line. Two simple case studies are presented, based on a Mercure product line and the banking product line, to illustrate the overall process, from the modeling of the product line to the product derivation.

RobotML, a domain-specific language to design, simulate and deploy robotic applications

A large number of robotic software have been developed but cannot or can hardly interoperate with each other because of their dependencies on specific hardware or software platform is hard-wired into the code. Consequently, robotic software is hard and expensive to develop because there is little opportunity of reuse and because low-level details must be taken into account in early phases. Moreover, robotic experts can hardly develop their application without programming knowledge or the help of programming experts and robotic software is difficult to adapt to hardware or target-platform changes. In this paper we report on the development of RobotML, a Robotic Modeling Language that eases the design of robotic applications, their simulation and their deployment to multiple target execution platforms.

Feature Identification from the Source Code of Product Variants

In order to migrate software products which are deemed similar into a product line, it is essential to identify the common features and the variations between the product variants. This can however be tedious and error-prone as it may involve browsing complex software and a lot of more or less similar variants. Fortunately, if arte facts of the product variants (source code files and/or models) are available, feature identification can be at least partially automated. In this paper, we thus propose a three-step approach to feature identification from source code of which the first two steps are automated.

Bottom-up adoption of software product lines: a generic and extensible approach

Although Software Product Lines are recurrently praised as an efficient paradigm for systematic reuse, practical adoption remains challenging. For bottom-up Software Product Line adoption, where a set of artefact variants already exists, practitioners lack end-to-end support for chaining (1) feature identification, (2) feature location, (3) feature constraints discovery, as well as (4) reengineering approaches. This challenge can be overcome if there exists a set of principles for building a framework to integrate various algorithms and to support different artefact types. In this paper, we propose the principles of such a framework and we provide insights on how it can be extended with adapters, algorithms and visualisations enabling their use in different scenarios. We describe its realization in BUT4Reuse (Bottom--Up Technologies for Reuse) and we assess its generic and extensible properties by implementing a variety of extensions. We further empirically assess the complexity of integration by reproducing case studies from the literature. Finally, we present an experiment where users realize a bottom-up Software Product Line adoption building on the case study of Eclipse variants.

Towards a language-independent approach for reverse-engineering of software product lines

Common industrial practices lead to the development of similar software products. These products are usually managed in an ad-hoc way which gradually results in a low product quality. To overcome this problem, it is essential to migrate these products into a Software Product Line (SPL). Towards this direction, this paper proposes a language-independent approach capable of reverse-engineering an SPL from the source code of product variants. A prototype tool and a case study show the feasibility and the practicality of the proposed approach.

Automating the Extraction of Model-Based Software Product Lines from Model Variants (T)

We address the problem of automating 1) the analysis of existing similar model variants and 2) migrating them into a software product line. Our approach, named MoVaPL, considers the identification of variability and commonality in model variants, as well as the extraction of a CVL-compliant Model-based Software Product Line (MSPL) from the features identified on these variants. MoVaPL builds on a generic representation of models making it suitable to any MOF-based models. We apply our approach on variants of the open source ArgoUML UML modeling tool as well as on variants of an In-flight Entertainment System. Evaluation with these large and complex case studies contributed to show how our feature identification with structural constraints discovery and the MSPL generation process are implemented to make the approach valid (i.e., the extracted software product line can be used to regenerate all variants considered) and sound (i.e., derived variants We address the problem of automating 1) the analysis of existing similar model variants and 2) migrating them into a software product line. Our approach, named MoVaPL, considers the identification of variability and commonality in model variants, as well as the extraction of a CVL-compliant Model-based Software Product Line (MSPL) from the features identified on these variants. MoVaPL builds on a generic representation of models making it suitable to any MOF-based models. We apply our approach on variants of the open source ArgoUML UML modeling tool as well as on variants of an In-flight Entertainment System. Evaluation with these large and complex case studies contributed to show how our feature identification with structural constraints discovery and the MSPL generation process are implemented to make the approach valid (i.e., the extracted software product line can be used to regenerate all variants considered) and sound (i.e., derived variants which did not exist are at least structurally valid).which did not exist are at least structurally valid).

Identifying and Visualising Commonality and Variability in Model Variants

Models, as any other software artifact, evolve over time during the development life-cycle. Different versions of the same model are thus existing at different times. Model comparison of different versions has received a lot of attention in recent years. However, existing techniques focus on comparing only two model versions at the same time to identify model differences. Independently of model versioning context, another dimension of variation, called variation in space, appears in models. Contrary to variation in time, variation in space means that a set of model variants exists and should be maintained. Comparing all these model variants to identify common and variable elements becomes thus a major challenge. Current approaches for model variants comparison lack of flexibility and appropriate visualisation paradigm. The contribution of this paper is the Model Variants Comparison approach (MoVaC). This approach compares a set of model variants and identifies both commonality and variability in the form of what is referred to as features. Each feature consists in a set of atomic model-elements. MoVaC also visualizes the identified features using a graphical representation where common and variable features are explicitly presented to users. We validate the approach on two use cases demonstrating the flexibility of MoVaC to be applied to any kind of EMF-based model variants.

Feature Relations Graphs: A Visualisation Paradigm for Feature Constraints in Software Product Lines

Software Product Line Engineering is a mature approach enabling the derivation of product variants by assembling reusable assets. In this context, domain experts widely use Feature Models as the most accepted formalism for capturing commonality and variability in terms of features. Feature Models also describe the constraints in feature combinations. In industrial settings, domain experts often deal with Software Product Lines with high numbers of features and constraints. Furthermore, the set of features are often regrouped in different subsets that are overseen by different stakeholders in the process. Consequently, the management of the complexity of large Feature Models becomes challenging. In this paper we propose a dedicated interactive visualisation paradigm to help domain experts and stakeholders to manage the challenges in maintaining the constraints among features. We build Feature Relations Graphs (Frogs) by mining existing product configurations. For each feature, we are able to display a Frog which shows the impact, in terms of constraints, of the considered feature on all the other features. The objective is to help domain experts to 1) obtain a better understanding of feature constraints, 2) potentially refine the existing feature model by uncovering and formalizing missing constraints and 3) serve as a recommendation system, during the configuration of a new product, based on the tendencies found in existing configurations. The paper illustrates the visualisation paradigm with the industrial case study of Renaults Electric Parking System Software Product Line.

ESPLA: A Catalog of Extractive SPL Adoption Case Studies

Building Software Product Lines (SPLs) from existing artefacts is known as the extractive approach for SPL adoption. The traditional case is that variants are created with ad-hoc reuse (e.g., copy-paste-modify to quickly respond to different customer needs) and practitioners want to reengineer them to an SPL. Several industrial cases have been presented in the literature to motivate the interest of the extraction and many case studies are used to validate methods and techniques for different activities during this adoption process. However, there is no catalog or repository that gather together case studies and artefacts related to extractive SPL adoption. In this paper we present ESPLA, a catalog of Extractive SPL Adoption case studies that aims to foster the advance of this field by providing comprehensive information about case studies that will be otherwise scattered in the literature. Researchers, practitioners and educators can use this catalog to find the case studies that better fit to their particular needs. Currently, ESPLA contains information about 123 case studies and it is intended to be a catalog that can be updated and extended by the community.