Research Of Active Services Component Composition Based On Web

Active service is a newly on-demand computing pattern based on the evolution of Web services.lt provides users with an integrated, intelligent and personalized Web services solutions. According to users'service requirements, search, discover and dig out the components that meet requirements of users from Internet or local network, and then assemble, compile and publish the service to users.The development of component technology provides the basis for realization of active service.There are many professional component libraries as Alphaworks, Componentplanet, Flashline, which provide many different components, such as JaveBean/EJB, COM/DCOM, CORBA in internet.However,for the difference of these components on the structure,component description and access methods, it is difficult to call each other and assemble to provide services for the uses.In order to solve the inconsistency of heterogeneous components,this paper presents the component packaging technology based on Web services.The heterogeneous components are enapsulated as Web services,and the Web services can be assembled, using the standard protocols, not platform-related,not linguistic-relate on of the Web service.The paper has three main parts.The first part describes the knowledge of Web services,component-related technologies and concepts and models of active service, and then explains the relation between active services and components, and the meaning and methods of component-based software development.The second part introduces the popular stage three component model CORBA,COM,and EJB,and then focuses on the specific process of the three components packaged Web service.The third part proposes the software development process of heterogeneous component and Web services,and the architecture model of component composition based on Web service,and Web services composition at first.Then,there is an instance of Web service composition.The purpose and significance of this paper to use componets encapsulated as Web services in Internet to shield the heterogeneous and inconsistent,and to provide a unified interface for the composition of components.Finally,this paper proposes the approach of Web services assembly based on BPEL to provide users with customized services.