World Wide Web Journal

With the adoption of service-oriented paradigm on the Web, many software services are likely to fulfil similar functional needs of the users. Service selection therefore becomes a key issue; especially in the emerging marketplaces of services context, which are mediating between service providers and service consumers. There is a huge research work on service selection; covering both functional based service selection and non functional based service selection. However, the selection process still relies on rules defined by the selection mechanism itself. This approach is not user-centric and does not enable the user to specify by himself the rules to apply during the selection process. This paper aims at providing such mechanism. Our approach is characterized by introducing the concept of abstract Widget; A graphical user interface that enables the user to first choose the rules to apply during the process of selecting software services at runtime, and second to execute the selected software service. The rules are defined through a language that enables to refer to heterogeneous parameters that could be pertinent in the selection process (e.g. service price, user location, and Qos). The abstract Widgets enable marketplace providers to expose functionalities instead of third party software services. This approach has been validated by designing, implementing, and testing an end-to-end architecture. This includes implementing several abstract Widgets, and considering several software services available today in the Web.