Abstract. Although a feature model can represent commonalities and variabilities in a very concise taxonomic form, features in a feature model are merely symbols. Mapping features to other models, such as behavioral or data specifications, gives them semantics. In this paper, we propose a general template-based approach for mapping feature models to concise representations of variability in different kinds of other models. We show how the approach can be applied to UML 2.0 activity and class models and describe a prototype implementation. 1

Abstract. Nowadays, object-oriented meta-languages such as MOF (Meta-Object Facility) are increasingly used to specify domain-specific languages in the model-driven engineering community. However, these meta-languages focus on structural specifications and have no built-in support for specifications of operational semantics. In this paper we explore the idea of using aspectoriented modeling to add precise action specifications with static type checking and genericity at the meta level, and examine related issues and possible solutions. We believe that such a combination would bring significant benefits to the community, such as the specification, simulation and testing of operational semantics of metamodels. We present requirements for such statically-typed meta-languages and rationales for the aforementioned benefits. 1

Modelling adaptive Web applications is a difficult and complex task. Usually, the development of general system functionality and context adaptation is intertwined. However, adaptivity is a cross-cutting concern of an adaptive Web application, and thus is naturally viewed as an aspect. Using aspect-oriented modelling techniques from the very beginning in the design of adaptive Web applications we achieve a systematic separation of general system functionality and context adaptation. We show the benefits of this approach by making navigation adaptive.

Access control is only inadequately supported by the common design methods for Web applications. We propose an aspect-oriented technique for solving this problem. Our approach is an extension of UML-based Web Engineering. UML state machines are used to specify the access control rules of navigation nodes. Aspectoriented modeling helps modularize the design.

The aspect oriented modeling (AOM) approach provides mechanisms for separating crosscutting functionality from core functionality in design models. Crosscutting functionality is described by aspect models and the core application functionality is described by a primary model. The integrated system view is obtained by composing the primary and aspect models. In this paper, we present a model composition technique that relies on signature matching: A model element is merged with another if their signatures match. A signature consists of some or all properties of an element as defined in the UML metamodel. The technique proposed in this paper is capable of detecting some conflicts that can arise during composition.

Access control features are often spread across and tangled with other functionality in a design. This makes modifying and replacing these features in a design difficult. Aspect-oriented modeling (AOM) techniques can be used to support separation of access control concerns from other application design concerns. Using an AOM approach, access control features are described by aspect models and other application features are described by a primary model. Composition of aspect and primary models yields a design model in which access control features are integrated with other application features. In this paper, we present, through an example, an AOM approach that supports verifiable composition of behaviors described in access control aspect models and primary models. Given an aspect model, a primary model, and a specified property, the composition technique produces proof obligations as the behavioral descriptions in the aspect and primary models are composed. One has to discharge the proof obligations to establish that the composed model has the specified property. Categories and Subject Descriptors

Variability management is a key concern in the software industry. It allows designers to rapidly propose applications that fit the environment and the user needs, with a certain Quality-of-Service level, by choosing adapted variants. While Aspect-Oriented Programming has been introduced for managing variability and complexity at the code level, the Software Product-Line community highlights the needs for variability in the earlier phases of the software lifecycle, where a system is generally described by means of models. In this paper, we propose a generic approach for weaving flexible and reusable aspects at a model level. By extending our generic Aspect-Oriented Modeling approach with variability, we can manage variability and complexity in the early phases of the software lifecycle. 1

Abstract. Large models for complex systems can be decomposed in separate pieces corresponding to different perspectives on the system. This decomposition allows the modeller to check properties locally on some aspects of the system before considering the global complexity of the model. In this paper we consider two types of decomposition: according to the concerns identified in the requirements and according to structural and behavioural perspectives. Once the separate models are available and have been checked separately, they have to be composed to check global properties. In this work, we propose automatic composition operators for symmetric and asymmetric concern models, each concern being modelled from a structural and behavioural point of view. 1

We propose bottom-up support for modeling crosscutting structure in UML by adding a simple join point model to the meta-model. This supports built-in crosscutting modeling constructs such as class and sequence diagrams, collaborations, and state machines. It also facilitates adding new kinds of crosscutting modeling constructs such inter-type declarations and advice. A simple planner tool produces a uniform representation of the crosscutting structure, which can then be displayed or analyzed in a variety of ways. We demonstrate a couple of simple automated analysis tools which take advantage of the exposed crosscutting structure. We also discuss how support for advice could be added to the meta-model and planner, and the semantic differences between advice in UML and AspectJ. ii Contents

In model driven development (MDD), specifying transformations between models at various levels of abstraction can be a complex task. Specifying transformations for pervasive system features that are tangled with other system features is particularly difficult because the elements to be transformed are distributed across a model. This paper presents an aspect oriented model driven framework (AOMDF) that facilitates separation of pervasive features and supports their transformation across different levels of abstraction. The framework is illustrated using an example in which a platform independent model of a banking application is transformed to a platform specific model. Keywords: Aspect-oriented software development, distributed applications, QVT, middleware, model driven development, separation of concerns, transactions, UML. 1