Transformation Techniques for OCL Constraints

Constraints play a key role in the definition of conceptual schemas. In the UML, constraints are usually specified by means of invariants written in the OCL. However, due to the high expressiveness of the OCL, the designer has different syntactic alternatives to express each constraint. The techniques presented in this paper assist the designer during the definition of the constraints by means of generating equivalent alternatives for the initially defined ones. Moreover, in the context of the MDA, transformations between these different alternatives are required as part of the PIM-to-PIM, PIM-to-PSM or PIM-to-code transformations of the original conceptual schema

UML-B and Event-B: an integration of languages and tools

UML-B is a graphical front end for Event-B. It adds support for class-oriented modelling but retains the Event-B concept of a closed system characterized by families of spontaneous events. UML-B is similar to UML but is essentially a new notation based on a separate meta-model. We provide tool support for UML-B, including drawing tools and a translator to generate Event-B models. The tools are closely integrated with the Event-B verification tools so that when a drawing is saved the translator automatically generates the corresponding Event-B model. The Event-B verification tools (syntax checker and prover) then run automatically providing an immediate display of problems. We introduce the UML-B notation its tool support and its integration with Event-B

Case study: Class diagram restructuring

This case study is an update-in-place refactoring transformation on UML class diagrams. Its aim is to remove clones of attributes from a class diagram, and to identify new classes which abstract groups of classes that share common data features. It is used as one of a general collection of transformations (such as the removal of redundant inheritance, or multiple inheritance) which aim to improve the quality of a specification or design level class diagram. The transformation is a typical example of a model refactoring, and illustrates the issues involved in such transformations.Comment: In Proceedings TTC 2013, arXiv:1311.753

Extending UML templates towards flexibility

UML templates are generic model elements that may be instantiated as domain specific solutions by means of parameterization. Some of the elements in a template definition are marked as parameters, implying that these must be sub-stituted by elements of the domain model, so to get a fully functional instance of the template. On parameter substitutions, UML enforces that the parame-tered element and its substitute must be of the same kind (both classes, both at-tributes, etc.). This paper shows that this constraint confines the applicability of templates and proposes an alternative that, by allowing substitutions among elements of different kinds, broadens that applicability. Cross-kind substitu-tions, however, require adequate semantics for the Binding relationship. Such semantics are proposed as model transformations that must complement the plain substitutions preconized by UML. Examples of such transformations are provided for activities in a template being expanded into a bound element.info:eu-repo/semantics/publishedVersio

A UML/OCL framework for the analysis of fraph transformation rules

In this paper we present an approach for the analysis of graph transformation rules based on an intermediate OCL representation. We translate different rule semantics into OCL, together with the properties of interest (like rule applicability, conflicts or independence). The intermediate representation serves three purposes: (i) it allows the seamless integration of graph transformation rules with the MOF and OCL standards, and enables taking the meta-model and its OCL constraints (i.e. well-formedness rules) into account when verifying the correctness of the rules; (ii) it permits the interoperability of graph transformation concepts with a number of standards-based model-driven development tools; and (iii) it makes available a plethora of OCL tools to actually perform the rule analysis. This approach is especially useful to analyse the operational semantics of Domain Specific Visual Languages. We have automated these ideas by providing designers with tools for the graphical specification and analysis of graph transformation rules, including a backannotation mechanism that presents the analysis results in terms of the original language notation

EMFtoCSP: A Tool for the Lightweight Verification of EMF Models

International audienceThe increasing popularity of MDE results in the creation of larger models and model transformations, hence converting the specification of MDE artefacts in an error-prone task. Therefore, mechanisms to ensure quality and absence of errors in models are needed to assure the reliability of the MDE-based development process. Formal methods have proven their worth in the verification of software and hardware systems. However, the adoption of formal methods as a valid alternative to ensure model correctness is compromised for the inner complexity of the problem. To circumvent this complexity, it is common to impose limitations such as reducing the type of constructs that can appear in the model, or turning the verification process from automatic into user assisted. Since we consider these limitations to be counterproductive for the adoption of formal methods, in this paper we present EMFtoCSP, a new tool for the fully automatic, decidable and expressive verification of EMF models that uses constraint logic programming as the underlying formalism

AuRUS: explaining the validation of UML/OCL conceptual schemas

The validation and the verification of conceptual schemas have attracted a lot of interest during the last years, and several tools have been developed to automate this process as much as possible. This is achieved, in general, by assessing whether the schema satisfies different kinds of desirable properties which ensure that the schema is correct. In this paper we describe AuRUS, a tool we have developed to analyze UML/OCL conceptual schemas and to explain their (in)correctness. When a property is satisfied, AuRUS provides a sample instantiation of the schema showing a particular situation where the property holds. When it is not, AuRUS provides an explanation for such unsatisfiability, i.e., a set of integrity constraints which is in contradiction with the property.Peer ReviewedPostprint (author’s final draft