The Data Access Middleware Design And Realization

With the swift development of Computer technology, the interaction among the different hardware, the different network and the different databases, the existence of multi modes existing, result in low efficiency, un-credible transmission and data-encryption and long development cycle. The traditional system and tools software can not solve such problems. But appearance of the middleware provides a better solution to these problems. Based on the discussion of middleware, the thesis consists of two parts: The discussion on middleware: this thesis demonstrates the history, the concept, the classification and the characteristics of middleware, and it discusses the general-used middleware, such as Data Access Middleware and Transaction Processing Middleware, and especially demonstrate the implementation mechanism and key technology of Data Access Middleware and. Application case: According to the above mechanism and key technology, we design and implement a Data Access Middleware. After we present the design target of the Data Access Middleware, this thesis demonstrates the main function of the Data Access Middleware, and gives the physical model, system architecture. This thesis demonstrates the design of the network interface and security problems of the network transmission. It emphasizes the key technology in development including the network transmission theory, thread pool technology, and how we realize the communication between client and middleware by WINSOCK in WINDOWS. And we discuss the realization of the network transmission interface and credible transmission. For the process of the business logic, this thesis discourses upon the flow of the process of the business logic, the scheduling of the middleware prior level queue. According to Improving Weighted Fair Queuing, we improve the performance of the system. According to adding the function of the accessing hetero-database on this middleware system, we can access diverse database transparently. This thesis discourses upon the design and realization of the data access. In this thesis, according to discussion of middleware technology we design and implement a data access middleware. Through the test we prove that middleware improves the system performance when clients reach certain number.