Towards an I/O Conformance Testing Theory for Software Product Lines based on Modal Interface Automata

We present an adaptation of input/output conformance (ioco) testing principles to families of similar implementation variants as appearing in product line engineering. Our proposed product line testing theory relies on Modal Interface Automata (MIA) as behavioral specification formalism. MIA enrich I/O-labeled transition systems with may/must modalities to distinguish mandatory from optional behavior, thus providing a semantic notion of intrinsic behavioral variability. In particular, MIA constitute a restricted, yet fully expressive subclass of I/O-labeled modal transition systems, guaranteeing desirable refinement and compositionality properties. The resulting modal-ioco relation defined on MIA is preserved under MIA refinement, which serves as variant derivation mechanism in our product line testing theory. As a result, modal-ioco is proven correct in the sense that it coincides with traditional ioco to hold for every derivable implementation variant. Based on this result, a family-based product line conformance testing framework can be established.Comment: In Proceedings FMSPLE 2015, arXiv:1504.0301

Model-based Quality Assurance of Cyber-Physical Systems with Variability in Space, over Time and at Runtime

Cyber-physical systems (CPS) are frequently characterized by three essential properties: CPS perform complex computations, CPS conduct control tasks involving continuous data- and signal-processing, and CPS are (parts of) distributed, and even mobile, communication systems. In addition, modern software systems like CPS have to cope with ever-growing extents of variability, namely variability in space by means of predefined configuration options (e.g., software product lines), variability at runtime by means of preplanned reconfigurations (e.g., runtime-adaptive systems), and variability over time by means of initially unforeseen updates to new versions (e.g., software evolution). Finally, depending on the particular application domain, CPS often constitute safety- and mission-critical parts of socio-technical systems. Thus, novel quality-assurance methodologies are required to systematically cope with the interplay between the different CPS characteristics on the one hand, and the different dimensions of variability on the other hand. This thesis gives an overview on recent research and open challenges in model-based specification and quality-assurance of CPS in the presence of variability. The main focus of this thesis is laid on computation and communication aspects of CPS, utilizing evolving dynamic software product lines as engineering methodology and model-based testing as quality-assurance technique. The research is illustrated and evaluated by means of case studies from different application domains

Conflict Detection for Edits on Extended Feature Models using Symbolic Graph Transformation

Feature models are used to specify variability of user-configurable systems as appearing, e.g., in software product lines. Software product lines are supposed to be long-living and, therefore, have to continuously evolve over time to meet ever-changing requirements. Evolution imposes changes to feature models in terms of edit operations. Ensuring consistency of concurrent edits requires appropriate conflict detection techniques. However, recent approaches fail to handle crucial subtleties of extended feature models, namely constraints mixing feature-tree patterns with first-order logic formulas over non-Boolean feature attributes with potentially infinite value domains. In this paper, we propose a novel conflict detection approach based on symbolic graph transformation to facilitate concurrent edits on extended feature models. We describe extended feature models formally with symbolic graphs and edit operations with symbolic graph transformation rules combining graph patterns with first-order logic formulas. The approach is implemented by combining eMoflon with an SMT solver, and evaluated with respect to applicability.Comment: In Proceedings FMSPLE 2016, arXiv:1603.0857

Improved Conflict Detection for Graph Transformation with Attributes

In graph transformation, a conflict describes a situation where two alternative transformations cannot be arbitrarily serialized. When enriching graphs with attributes, existing conflict detection techniques typically report a conflict whenever at least one of two transformations manipulates a shared attribute. In this paper, we propose an improved, less conservative condition for static conflict detection of graph transformation with attributes by explicitly taking the semantics of the attribute operations into account. The proposed technique is based on symbolic graphs, which extend the traditional notion of graphs by logic formulas used for attribute handling. The approach is proven complete, i.e., any potential conflict is guaranteed to be detected.Comment: In Proceedings GaM 2015, arXiv:1504.0244

Software Engineering Challenges for Quantum Computing: Report from the First Working Seminar on Quantum Software Engineering (WSQSE 22)

The First Working Seminar on Quantum Software Engineering (WSQSE 2022) took place on December 15 and 16, 2022 in Innsbruck, Austria. An audience of 33 quantum computing and software engineering researchers and practitioners joined the two-day event. The workshop enabled us to foresee short-term and longterms perspectives of Quantum Software Engineering, as well as a set of requirements, issues, and challenges for architecting, programming, and testing Quantum Software Engineering applications. In this report, we provide the summary of the workshop, by reporting on the structure of the event and the main results coming from the sessions and working groups

A comprehensive description of a model-based, continous development process for AUTOSAR systems with integrated quality assurance

Der AUTOSAR-Standard definiert neben einer durchgängig werkzeuggestützten und modellbasierten Methodik zur Entwicklung von Steuergeräte-Software eine technische Infrastruktur als standardisierte Steuergeräte-Basissoftware zur Implementierung dieser Systeme im Automobil. Die wesentlichen Herausforderungen in der Entwicklung automotiver Systeme ergeben sich dabei nicht nur aus der stetig steigenden Menge korrekt umzusetzender Funktionalität, sondern auch aus der wachsenden Anzahl zusätzlich zu erfüllender Qualitätsanforderungen, wie z.B. Sicherheit, Performanz oder Kosten. Die Integration von Ansätzen zur frühzeitigen, Entwicklungsphasen begleitenden Überprüfung von Korrektheits- und Qualitätskriterien kann dabei maßgeblich zur Beherrschbarkeit der Komplexität dieser Systeme beitragen. Es wird ein entsprechend durchgängig werkzeuggestützter und modellbasierter Entwicklungsprozess, basierend auf dem V-Modell sowie dessen Integration in die AUTOSAR-Methodik definiert. Neben der Überprüfung der funktionalen Korrektheit durch systematische Testverfahren sieht das erweiterte Prozessmodell die Bewertung beliebiger Qualitätskriterien für das zu entwickelnde System vor. Es wird beschrieben, wie insbesondere im AUTOSAR-Kontext der Entwurf der Systemarchitektur die hierfür entscheidende Design-Phase darstellt und als Grundlage für Qualitätsabschätzungen durch Architektur-Evaluation dienen kann. Die Vorgehensweise in den einzelnen Entwicklungsschritten wird detailliert anhand einer umfangreichen, vollständig AUTOSAR-konformen Fallstudie, bestehend aus einem vereinfachten PKW-Komfortsystem, demonstriert. Die durchgängige Toolkette umfasst alle Phasen von der Anforderungsspezifikation bis zur Implementierung auf einem prototypischen Hardware-Demonstrator bestehend aus vier über CAN vernetzten Steuergeräten und HIL-Schnittstellen für die Testdurchführung. Es wird auf ausgewählte Implementierungsdetails, notwendige Workarounds und Besonderheiten der prototypischen Umsetzung eingegangen.The AUTOSAR standard defines a seamless tool supported and model based methodology for ECU software design and engineering. Furthermore, the standard specifies a technical infrastructure by means of standardized basic software modules for ECU networks, serving as a uniform implementation platform for AUTOSAR systems. The major challenges in automotive systems development not only arise as a result of the contiuously growing amount of functionality to be realized correctly, but also from the increasing number of quality requirements to be taken into account, e.g. safety, performance, and costs. The integration of approaches for early checking of correctness and quality criteria accompanying the different development phases makes a significant contribution towards coping with the complexity of such systems. We describe such a model based development process and a corresponding tool chain based on the V-modell and its embedding into the AUTOSAR methodology. For the validation of functional correctness systematic testing approaches are applied, and for quality criteria according evaluation methods are used. We discuss that especially in the context of AUTOSAR, the phase of architectural system design is crucial for the quality properties of the system under development, and to what extent architecture evaluation can be used for quality estimation. The practices in the different development steps are illustrated in detail by means of a comprehensive, AUTOSAR compliant case study, i.e. a body comfort system. The tool chain proposed comprises all development stages, starting from the requirements specification, and concluding with the system implementation on a hardware demonstrator prototype. The demonstrator consists of ECUs coupled via CAN, as well as HIL interfaces for test case applications. We give detailled insights in selected impl. issues, workarounds required, and the configuration steps needed for the AUTOSAR operating system. A discussion of the pro's and con's regarding the potential of AUTOSAR concludes