Research And Implementation Of Web Service Composition Based On WSDL Extension

SOA (Service-Oriented Architecture), as a new generation of software architec-ture, has loosely coupled, open, platform and language independent features. It pro-vides an effective solution for reuse of services and business integration and interac-tion of the cross-platform and has obtained considerable attention from both research and practice realms. As SOA gradually matures, services emerge at an ever-increasing pace in Internet.As SOA technology matures, it brings out a number of component services, on which based, and composition methods. In order to enhance the efficiency of design-ing and developing software or system architecture, we should try our best to exploit and compose numeral existed primitive and composed services on internet which ab-solutely make contributes to service computing ability. In general, service composi-tion means, in the context of composite services, different primitive services can composed together to satisfy one goal service, which still guarantees essential charac-ters of the composite service. Service composition becomes a scientific issue.However, domestic and international previous related studies mostly are based on the assumption that component services and composite services require some kind of formal description of service behavior. But in the web service application, the most common form in SOA, the standard service contract cannot guarantee to satisfy this necessary condition. According to the specification of W3C and the majority of prac-tices of existing SOAP-based Web services, validation analysis of the services pro-vider, requestor and third-partly can only obtains the invoked interfaces and the input and output messages described in WSDL. So in the case of limited information from WSDL, this paper begins the study of service composition.Aim at the above-mentioned problems, this paper does the following three as-pects of the study and obtains the corresponding research results.1. Proposed an effective method to extend the behavior of services in WSDL based on the documentation of services;2. Further depth to rule of how to automatically and collaboratively extend the behavior of services on the basis of the GUI editor which largely applies convenienc-es to provider, customers and the third parts;3. In more detail to develop the automatic tool based on Axis2architecture to produce the client of service with behavior from WSDL++documentation; 4. Achieved different primitive services from Seekda and Xmethod register and test our research method by classic K-lookahead algorithm.