Systematic model-driven design and early validation enable engineers to verify that a reactive system does not violate its requirements before actually implementing it. Requirements may come from multiple stakeholders, who are often concerned with different facets – design typically involves different experts having different concerns and views of the system. Engineers start from a specification which may be sourced from some domain model, while validation is often done on state-transition structures that support model checking. Two computationally expensive steps may work against scalability: transformation from specification to state-transition structures, and model checking. We propose a technique that makes the former efficient and also makes the resulting transition systems small enough to be efficiently verified. The technique automatically projects the specification into submodels depending on a property sought to be evaluated, which captures some stakeholder’s viewpoint. The resulting reactive system submodel is then transformed into a state-transition structure and verified. The technique achieves cone-of-influence reduction, by slicing at the specification model level. Submodels are analysis-equivalent to the corresponding full model. If stakeholders propose a change to a submodel based on their own view, changes are automatically propagated to the specification model and other views affected. Automated reflection is achieved thanks to bidirectional model transformations, ensuring correctness. We cast our proposal in the context of graph-based reactive models whose dynamics is described by rewriting rules. We demonstrate our view-based framework in practice on a case study within cyber-physical systems.

Christos Tsigkanos

TU Vienna

Austria

NIANYU LI

Peking University, China

China

Zhi Jin

Peking University

Zhenjiang Hu

Peking University, China

Carlo Ghezzi

Politecnico di Milano

Italy

Signal-based temporal properties (SBTPs) characterize the behavior of a system when its inputs and outputs are signals over time; they are very common for the requirements specification of cyber-physical systems. Although there exist several specification languages for expressing SBTPs, such languages either do not easily allow the specification of important types of properties (such as spike or oscillatory behaviors), or are not supported by (efficient) trace-checking procedures.

In this paper, we propose SB-TemPsy, a novel model-driven trace-checking approach for SBTPs. SB-TemPsy provides (i) SB-TemPsy-DSL, a domain-specific language that allows the specification of SBTPs covering the most frequent requirement types in cyber-physical systems, and (ii) SB-TemPsy-Check, an efficient, model-driven trace-checking procedure. This procedure reduces the problem of checking an SB-TemPsy-DSL property over an execution trace to the problem of evaluating an Object Constraint Language constraint on a model of the execution trace.

We evaluated our contributions by assessing the expressiveness of SB-TemPsy-DSL and the applicability of SB-TemPsy-Check using a representative industrial case study in the satellite domain. SB-TemPsy-DSL could express 97% of the requirements of our case study and SB-TemPsy-Check yielded a trace-checking verdict in 87% of the cases, with an average checking time of 48.7 s. From a practical standpoint and compared to state-of-the-art alternatives, our approach strikes a better trade-off between expressiveness and performance as it supports a large set of property types that can be checked, in most cases, within practical time limits.

Chaima Boufaied

University of Luxembourg

Claudio Menghi

University of Luxembourg, Luxembourg

Domenico Bianculli

University of Luxembourg

Luxembourg

Lionel Briand

SnT Centre/University of Luxembourg

Luxembourg

Yago Isasi Parache

LuxSpace

High-fidelity Graphical User Interface (GUI) prototyping is a well-established and suitable method for enabling fruitful discussions, clarification and refinement of requirements formulated by customers. GUI prototypes can help to reduce misunderstandings between customers and developers, which may occur due to the ambiguity comprised in informal Natural Language (NL). However, a disadvantage of employing high-fidelity GUI prototypes is their time-consuming and expensive development. Common GUI prototyping tools are based on combining individual GUI components or manually crafted templates. In this work, we present GUI2WiRe, a tool that enables users to retrieve GUI prototypes from a semi-automatically created large-scale GUI repository for mobile applications matching user requirements specified in Natural Language (NLR). We extract multiple text segments from the GUI hierarchy data and employ various Information Retrieval (IR) models and Automatic Query Expansion (AQE) techniques to achieve ad-hoc GUI retrieval from NLR. Retrieved GUI prototypes mined from applications can be inserted in the graphical editor of GUI2WiRe to rapidly create wireframes. GUI components are extracted automatically from the GUI screenshots and basic editing functionality is provided to the user. Finally, a preview of the application is created from the wireframe to allow interactive exploration of the current design. We evaluated the applied IR and AQE approaches for their effectiveness in terms of GUI retrieval relevance on a manually annotated collection of NLR and discuss our planned user studies.

Kristian Kolthoff

Institute for Enterprise Systems (InES), University Of Mannheim

Germany

Christian Bartelt

Institute for Software and Systems Engineering, TU Clausthal

Simone Paolo Ponzetto

Data and Web Science Group, University of Mannheim