Enforced generative patterns for the specification of the syntax and semantics of visual languages

This is the author’s version of a work that was accepted for publication in Journal of Visual Languages and Computing. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Visual Languages and Computing,19, 4 (2008) DO: 10.1016/j.jvlc.2008.04.004Selected Papers from IEEE Symposium on Visual Languages and Human Centric Computing 2007 (VL/HCC 2007)We present the new notion of enforced generative pattern, a structure that declares positive or negative conditions that must be satisfied by a model. Patterns are applied to transformation rules resulting in new rules that modify models according to the pattern specification. In the case of a negative pattern, an application condition is added to the rule. In the case of a positive one, the rule is modified to consider additional context in its left-hand side and to increase its effects. We have defined these patterns in an abstract setting, which enables their instantiation for different structures, like graphs, triple graphs and graph transformation rules. We apply the previous concepts to the specification of the syntax and semantics of visual languages. In particular, we show instantiations for: (i) graphs, with applications at the syntactical level; (ii) triple graphs, for the coordination of syntax and static semantics; and (iii) rules, for the incremental construction of execution rules. We present some examples that illustrate the usefulness of the combination of these three instantiations. In particular, we show the specification of environments for visual languages with token-holder semantics, discrete-event semantics and communication semantics.Work supported by the Spanish Ministry of Education and Science, projects MOSAIC (TSI2005-08225-C07-06) and MODUWEB (TIN2006-09678). We thank the referees for their detailed and useful com- ments, which helped us in improving the paper

Resource-based enactment and adaptation of workflows from activity diagrams

Workflow management deals with different types of dependencies among tasks, in particular data- and policy-driven. The ability to reason on dependencies of different type allows workflow designers to consider different alternatives, or to define customized flows, reducing non-determinism. We propose a resource-centered view, in which both data-dependency between tasks and plan-dependent ordering of tasks are expressed as production and consumption of resources. This view is translated into a rule-based formalism, expressed in terms of multi-set rewriting for workflow enactment. In turn, rules are themselves seen as resources, so that they are prone to the same rewriting process, in order to redefine process schemas. We show how workflows expressed as activity diagrams can be translated to the proposed formalism, exploiting enforced generative patterns applied to triple graph grammars, and how redefinition of workflow processes can occur through typical patterns of adaptation. We also discuss possible concrete syntaxes for the obtained rules

Clafer: Lightweight Modeling of Structure, Behaviour, and Variability

Embedded software is growing fast in size and complexity, leading to intimate mixture of complex architectures and complex control. Consequently, software specification requires modeling both structures and behaviour of systems. Unfortunately, existing languages do not integrate these aspects well, usually prioritizing one of them. It is common to develop a separate language for each of these facets. In this paper, we contribute Clafer: a small language that attempts to tackle this challenge. It combines rich structural modeling with state of the art behavioural formalisms. We are not aware of any other modeling language that seamlessly combines these facets common to system and software modeling. We show how Clafer, in a single unified syntax and semantics, allows capturing feature models (variability), component models, discrete control models (automata) and variability encompassing all these aspects. The language is built on top of first order logic with quantifiers over basic entities (for modeling structures) combined with linear temporal logic (for modeling behaviour). On top of this semantic foundation we build a simple but expressive syntax, enriched with carefully selected syntactic expansions that cover hierarchical modeling, associations, automata, scenarios, and Dwyer's property patterns. We evaluate Clafer using a power window case study, and comparing it against other notations that substantially overlap with its scope (SysML, AADL, Temporal OCL and Live Sequence Charts), discussing benefits and perils of using a single notation for the purpose

A Design Pattern for Executable DSML

Model executability is now a key concern in model-driven engineering, mainly to support early validation and verification (V&V). Some approaches have allowed to weave executability into metamodels, defining executable domain-specific modeling languages (DSML). Then, model validation may be achieved by direct interpretation of the conforming models. Other approaches address model executability by model compilation, allowing to reuse the virtual machines or V&V tools existing in the target domain. Nevertheless, systematic methods are not available to help the language designer in the definition of such an execution semantics and related support tools. For instance, simulators are mostly hand-crafted in a tool specific manner for each DSML. In this paper, we propose to reify the elements commonly used to support execution in a DSML. We infer a design pattern (called Executable DSML pattern) providing a general reusable solution for the expression of the executability concerns in DSML. It favors flexibility and improves reusability in the definition of semantics-based tools for DSML. We illustrate how this pattern can be applied to V&V and models at runtime, and give insights on the development of generic and generative tools for model animators

Early aspects: aspect-oriented requirements engineering and architecture design

This paper reports on the third Early Aspects: Aspect-Oriented Requirements Engineering and Architecture Design Workshop, which has been held in Lancaster, UK, on March 21, 2004. The workshop included a presentation session and working sessions in which the particular topics on early aspects were discussed. The primary goal of the workshop was to focus on challenges to defining methodical software development processes for aspects from early on in the software life cycle and explore the potential of proposed methods and techniques to scale up to industrial applications

Pattern-Based Development of Domain-Specific Modelling Languages

Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. A. Pescador, A. Garmendia, E. Guerra, J. Sánchez Cuadrado and J. de Lara, "Pattern-based development of Domain-Specific Modelling Languages," Model Driven Engineering Languages and Systems (MODELS), 2015 ACM/IEEE 18th International Conference on, Ottawa, ON, 2015, pp. 166-175. doi: 10.1109/MODELS.2015.7338247Model-Driven Engineering (MDE) promotes the use of models to conduct all phases of software development in an automated way. Models are frequently defined using Domain- Specific Modelling Languages (DSMLs), which many times need to be developed for the domain at hand. However, while constructing DSMLs is a recurring activity in MDE, there is scarce support for gathering, reusing and enacting knowledge for their design and implementation. This forces the development of every new DSML to start from scratch. To alleviate this problem, we propose the construction of DSMLs and their modelling environments aided by patterns which gather knowledge of specific domains, design alternatives, concrete syntax, dynamic semantics and functionality for the modelling environment. They may have associated services, realized via components. Our approach is supported by a tool that enables the construction of DSMLs through the application of patterns, and synthesizes a graphical modelling environment according to them.Work supported by the Spanish MINECO (TIN2011-24139 and TIN2014-52129-R), the R&D programme of the Madrid Region (S2013/ICE-3006), and the EU commission (FP7-ICT-2013-10, #611125)

Formalizing graphical notations

The thesis describes research into graphical notations for software engineering, with a principal interest in ways of formalizing them. The research seeks to provide a theoretical basis that will help in designing both notations and the software tools that process them. The work starts from a survey of literature on notation, followed by a review of techniques for formal description and for computational handling of notations. The survey concentrates on collecting views of the benefits and the problems attending notation use in software development; the review covers picture description languages, grammars and tools such as generic editors and visual programming environments. The main problem of notation is found to be a lack of any coherent, rigorous description methods. The current approaches to this problem are analysed as lacking in consensus on syntax specification and also lacking a clear focus on a defined concept of notated expression. To address these deficiencies, the thesis embarks upon an exploration of serniotic, linguistic and logical theory; this culminates in a proposed formalization of serniosis in notations, using categorial model theory as a mathematical foundation. An argument about the structure of sign systems leads to an analysis of notation into a layered system of tractable theories, spanning the gap between expressive pictorial medium and subject domain. This notion of 'tectonic' theory aims to treat both diagrams and formulae together. The research gives details of how syntactic structure can be sketched in a mathematical sense, with examples applying to software development diagrams, offering a new solution to the problem of notation specification. Based on these methods, the thesis discusses directions for resolving the harder problems of supporting notation design, processing and computer-aided generic editing. A number of future research areas are thereby opened up. For practical trial of the ideas, the work proceeds to the development and partial implementation of a system to aid the design of notations and editors. Finally the thesis is evaluated as a contribution to theory in an area which has not attracted a standard approach

Visual Specification Patterns

Visual modelling notations such as constraint diagrams can be used for the behavioural specifications of software components. This includes specifying invariants on classes or types and preconditions and postconditions of operations. However, one current problem in specifying components comes from the fact that editing constraints manually is time consuming and error prone and so we may adopt a pattern-based approach to alleviate this problem. One way to simplify the definition of constraints is to identify and capture those recurring constraints in the form of visual specification patterns. Such patterns would facilitate the automatic generation of diagrammatic constraints. This paper identifies some specification patterns that frequently occur when specifying software components and provides a diagrammatic representation of these patterns. This will form the basis of a library of specification patterns that could be used in the context of tools. We also show how such patterns can be combined in order to specify more complex constraints

1st doctoral symposium of the international conference on software language engineering (SLE) : collected research abstracts, October 11, 2010, Eindhoven, The Netherlands

The first Doctoral Symposium to be organised by the series of International Conferences on Software Language Engineering (SLE) will be held on October 11, 2010 in Eindhoven, as part of the 3rd instance of SLE. This conference series aims to integrate the different sub-communities of the software-language engineering community to foster cross-fertilisation and strengthen research overall. The Doctoral Symposium at SLE 2010 aims to contribute towards these goals by providing a forum for both early and late-stage Ph.D. students to present their research and get detailed feedback and advice from researchers both in and out of their particular research area. Consequently, the main objectives of this event are: – to give Ph.D. students an opportunity to write about and present their research; – to provide Ph.D. students with constructive feedback from their peers and from established researchers in their own and in different SLE sub-communities; – to build bridges for potential research collaboration; and – to foster integrated thinking about SLE challenges across sub-communities. All Ph.D. students participating in the Doctoral Symposium submitted an extended abstract describing their doctoral research. Based on a good set of submisssions we were able to accept 13 submissions for participation in the Doctoral Symposium. These proceedings present final revised versions of these accepted research abstracts. We are particularly happy to note that submissions to the Doctoral Symposium covered a wide range of SLE topics drawn from all SLE sub-communities. In selecting submissions for the Doctoral Symposium, we were supported by the members of the Doctoral-Symposium Selection Committee (SC), representing senior researchers from all areas of the SLE community.We would like to thank them for their substantial effort, without which this Doctoral Symposium would not have been possible. Throughout, they have provided reviews that go beyond the normal format of a review being extra careful in pointing out potential areas of improvement of the research or its presentation. Hopefully, these reviews themselves will already contribute substantially towards the goals of the symposium and help students improve and advance their work. Furthermore, all submitting students were also asked to provide two reviews for other submissions. The members of the SC went out of their way to comment on the quality of these reviews helping students improve their reviewing skills