On the interpretation of binary associations in the Unified Modelling Language

Binary associations between classifiers are among the most fundamental of UML concepts. However, there is considerable room for disagreement concerning what an association is, semantically; it turns out that at least two di#erent notions are called Associations. This confusion of concepts gives rise to unnecessary complication and ambiguity in the language, which have implications for the modeller because they can result in serious misunderstandings of static structure diagrams; similarly, they have implications for tool developers. In this paper we explore these issues, suggest improvements and clarifications, and demonstrate side-benefits that would accrue

On a Graph-Based Semantics for UML Class and Object Diagrams

In this paper we propose a formal extension of type graphs with notions that are commonplace in the UML and have long proven their worth in that context: namely, inheritance, multiplicity, containment and the like. We believe the absence of a comprehensive and commonly agreed upon formalisation of these notions to be an important and, unfortunately, often ignored omission. Since our eventual aim (shared by many researchers) is to give unambiguous, formal semantics to the UML using the theory of graphs and graph transformation, in this paper we propose a set of definitions to repair this omission. With respect to previous work in this direction, our aim is to arrive at more comprehensive and at the same time simpler definitions.\u

On the semantics of redefinition, specialization and subsetting of associations in UML (extended version)

The definition of the exact meaning of conceptual modeling concepts is considered a relevant issue since it enhances their effective and appropriate use by designers and facilitates the automatic processing of the models where they are included. Three related concepts that permit to improve the definition of an association in UML and which still lack of a formal semantic definition are: association redefinition, association specialization and association subsetting. This paper formalizes their semantics and points out the similarities and differences that exist among them. The formalization we propose is based on the meta-modelling approach and a semantic domain composed of a set of basic UML concepts and OCL expressions, which have a previous formal definition in the literature and which are well-understood.Preprin

A subset of precise UML for Model-based Testing

This paper presents an original model-based testing approach that takes a UML behavioural view of the system under test and automatically generates test cases and executable test scripts according to model coverage criteria. This approach is embedded in the LEIRIOS Test Designer tool and is currently deployed in domains such as Enterprise IT and electronic transaction applications. This model-based testing approach makes it possible to automatically produce the traceability matrix from requirements to test cases as part of the test generation process. This paper defines the subset of UML used for model-based testing and illustrates it using a small example

Subjects, Models, Languages, Transformations

Discussions about model-driven approaches tend to be hampered by terminological confusion. This is at least partially caused by a lack of formal precision in defining the basic concepts, including that of "model" and "thing being modelled" - which we call subject in this paper. We propose a minimal criterion that a model should fulfill: essentially, it should come equipped with a clear and unambiguous membership test; in other words, a notion of which subjects it models. We then go on to discuss a certain class of models of models that we call languages, which apart from defining their own membership test also determine membership of their members. Finally, we introduce transformations on each of these layers: a subject transformation is essentially a pair of subjects, a model transformation is both a pair of models and a model of pairs (namely, subject transformations), and a language transformation is both a pair of languages and a language of model transformations. We argue that our framework has the benefits of formal precision (there can be no doubt about whether something satifies our criteria for being a model, a language or a transformation) and minimality (it is hard to imagine a case of modelling or transformation not having the characterstics that we propose)

UML for the Semantic Web: Transformation-Based Approaches

The perspective role of UML as a conceptual modelling language for the Semantic Web has become an important research topic. We argue that UML could be a key technology for overcoming the ontology development bottleneck thanks to its wide acceptance and sophisticated tool support. Transformational approaches are a promising way of establishing a connection between UML and web-based ontology languages. We compare some proposals for defining transformations between UML and web ontology languages and discuss the different ways they handle the conceptual differences between these languages. We identify commonalities and differences of the approaches and point out open questions that have not or not satisfyingly been addressed by existing approaches

FV-RAD : a practical framework for rapid application development

Estágio realizado na OPT-Optimização e Planeamento de Transportes, S.ATese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 200