| This paper mostly introduces the application of middleware technology in telecom system, The development of Middleware Technology,necessity and superiority, and set forth the utility implement of The MiddleWare Telenology,include MiddleWare 's basic element composition, Work Flow, And discuss how to Choose of Database Interface, design mode, development Platform and The embody implement In YunNan Unicom Data integration network manage Performance SubSystem. DataBase MiddleWare implements Various logical manipulations in DataBase ,It Provides a Bridge For Client And Datebase Server Via interferce Mode.DataBase MiddleWare is designed to adopting EJB technology ,EJB is a distributing Model frame base on Middleware development,It includes operation Logical's repeat use Unit,allow detach application program logical and system Server ,in this way ,The developer can concentrate on operation Logical ,However ,many complex Affair such as distributing protocol,state manager and so on deliver to Server transact,there are "Write once ,Run everywhere" peculiarity,EJB compose structure is compose of Home Interface,Remote Interface,Bean implement class,Home interface answer for control the operation of Bean lifecycle,Create ,delete and find Bean,the Remote Interface defines the operation methods which will provoid to client,Bean implement class defines the implement detail of all operation logicals.there are three types Bean:Session Bean ,entity Bean and message driver Bean .In the process of design,considering the agility nature And high replant nature of the system ,we adopt mostly session Bean to design the middleware.JNDI is Java Naming And Catalogue Interface in J2EE platform,J2EE application program make use of JNDI to look up create EJB's Interface And JDBC Connection ,When the client transfer database Middleware,it look up the Remote Interface of EJB middleware via JNDI,find the implement class via Remote Interface,accordingly transfer database middleware to implement various data processing.In common use, The Database Accessing Interface have CGI, WEB API ,ODBC,JDBC and so on,The CGI cann't sustain data comprell access,namely CGI program cann't share by many client request,when CGI accept a client request ,Even if a CGI program is running ,also must restart a same instance,i.e to create a combine process,the more that combine request,the more which to need to create combine process,engross a great deal of memory,restrict the need memory resource of application program itself, Morever,every request create a process will consume a good many time,in multiuser application which need more Database connection ,Adopting CGI to connect Database will increase the wait time of connect database while the user increase,cause to system performance reduce,as a result ,The system will breakdown. WEB API can only function on special WEB Server and operation system,which cann't replant each other; ODBC is a standard interface of database access,It sets up a set of criterions,and provides a set of standard API (Application Programming Interface) for database access ,so the application program can access the data which save in various differ database manage system via ODBC API.moreover regardless every DBMS use what data sava format and programme interface .But It hasn't optimize DataSource ,can influence on database storage and reduce speed,Also only can using in relation database.As a result ,It is very difficult to access object database and other not ralation database by ODBC . JDBC is a Java language database access interface that can execute SQL sentences. It is compose of some Java language write class and interface.JDBC provides a standard application program design interface for database application program developer and database platform tool developer,So the developer can write full database application program by using pure Java language.Due to the Java language is independent of platform,so The program of access database who is write by JDBCAPI have very good currency s...
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