Dhouha Ayed

UniTI: a unified transformation infrastructure

A model transformation can be decomposed into a sequence of subtransformations, i.e. a transformation chain, each addressing a limited set of concerns. However, with current transformation technologies it is hard to (re)use and compose subtransformations without being very familiar with their implementation details. Furthermore, the difficulty of combining different transformation technologies often thwarts choosing the most appropriate technology for each subtransformation. In this paper we propose a model-based approach to reuse and compose subtransformations in a technology-independent fashion. This is accomplished by developing a unified representation of transformations and facilitating detailed transformation specifications. We have implemented our approach in a tool called UniTI, which also provides a transformation chain editor. We have evaluated our approach by comparing it to alternative approaches.

MDD approach for the development of context-aware applications

Context-aware systems offer entirely new opportunities for application developers and for end users by gathering context information and adapting systems behavior accordingly. Several context models have been defined and various context-aware middleware has been developed in order to simplify the development of context-aware applications. Unfortunately, the development of an application by using these middleware products introduces several technical details in the application. These technical details are specific to a given middleware and reduce the possibility of reusing the application on other middleware. In this paper, we propose an MDD (Model Driven Development) approach that makes it possible to design context-aware applications independently of the platform. This approach is based on several phases that approach step by step the context platform and allow designers to automatically map their models to several platforms through the definition of automatic and modular transformations. To be able to apply this approach we define a new UML profile for context-aware applications, that we use to explore our approach.

UML profile for the design of a platform-independent context-aware applications

Context-aware systems offer entirely new opportunities for application developers and for end users by gathering context information and adapting systems behavior accordingly. Several context models have been defined and various context-aware middleware has been developed in order to simplify the development of context-aware applications. Unfortunately, the development of an application by using these middleware products introduces several technical details in the application. These technical details are specific to a given middleware and reduce the possibility to reuse the application on other middleware. Our goal is to propose an MDD (Model Driven Development) approach that makes it possible to design context-aware applications independently from the platform. For this purpose, we propose a UML profile that allows context-aware application designers to specify the contexts that impact an application and the variability of an application model according to this context independently from the platform.

CADeComp: Context-aware deployment of component-based applications

The expansion of wireless communication and mobile hand-held devices makes it possible to deploy a broad range of applications on mobile terminals such as PDAs and mobile phones. The constant context changes of mobile users oblige them to carry out many deployment tasks of the same application in order to obtain an application whose configuration satisfies the context requirements. The difficulty and the frequency of these deployment tasks led us to study the deployment in a mobile environment and to look for a solution for the automation of the deployment adaptation to the context. This paper studies the deployment sensitivity to the context in order to identify the variable deployment parameters and to analyze the impact of the deployment adaptation on the production life cycle of applications. The contribution made by this paper consists in an innovative middleware entity called Context-Aware Deployment of COMPonents (CADeComp), which can be plugged into existing middleware deployment services. CADeComp defines a flexible data model that facilitates the tasks of component producers and application assemblers by allowing them to specify the meta-information required to adapt the deployment to the context. The advantage of CADeComp is that it is based on reliable adaptive mechanisms that are defined by a platform-independent model according to the MDA approach. We propose a mapping of the CADeComp model to CCM. CADeComp was implemented and evaluated on this platform.

Dynamic adaptation of CORBA component-based applications

An important requirement for pervasive computing systems is the ability to adapt at runtime to handle varying resources, user mobility, and changing user needs. In this paper, we present an innovative approach to adapt the CORBA component-based applications. This approach proposes to extend the CORBA deployment model to describe the variability of the architecture of applications and to extend the CORBA execution model in order to support adaptation at runtime. The originality of this approach is to consider the adaptation activities as non-functional aspects and to integrate them in the CORBA container.