Design And Mplementation Of Dynamic Invocation Execution Engine For Implemen- Tation-technology-independent Web Services

In the field of network management, with the rapid development of Internet technology, there will be more and more application scenarios for Web Services technology. There are variety of ways to the realization of a Web Services, with the increasing number of Web services, sometimes we need to call services that implemented in different ways. As a result, the service-to-service relationship becomes more complex. The limitation of static invocation is that a client can only call the corresponding service,and the clients bound to the platform are easily limited by the platform and affect the scope of application of the client. When using traditional dynamic invocation for calling service with user-defined data structure,the client needs to use compiled file from the server to construct this data type.In order to realize the dynamic invocation of services implemented by different technologies, and deal with the user-defined data types more conveniently, this thesis designs a dynamic invocation execution engine to meet the above requirements. The execution engine is a complete service call system, including two parts. First, client to complete the function of dynamic invocation. Second, interface-data processing system to complete the function of parsing and storing WSDL document.First,the client is inspired by the invocation way of document in Axis2 client.At the bottom of the service invocation, data transferred through the SOAP protocol. Therefore, if complex data structures stored in XML format, a SOAP request will be easily constructed inside the client, and then send to the server to complete the function of dynamic invocation. In other words, when service parameters come in XML format, the encapsulation, transmission and other operations for SOAP message will be completed inside. So the service caller does not need to know the internal structure of the server-side user-defined data type, just treat them as a whole.The goal of interface-data processing system is to support the function of client better, providing query interface of necessary information for client and query function with front-end interface for users. Except providing query-related functions, there are two important functions in this system, analysis and storage of WSDL document.For execution engine, dynamic invocation client is the main part,and the interface-data processing system provides the necessary support and additional function for the client. The two parts complement each other, and achieve the function of implementation-technology-independent dynamic invocation.