Corba-based Distributed Technology And Its Application In The Wuhan Roads&Bridges Management Systems

In the network age, in order to implement the reserved information resources conveniently and effectively and reduce the cost, the best way is to complete mutual mappings of different network and transparent interlinkings of client through certain mode . So the CORBA technology appeared and has been developed quickly. The CORBA technology is independent of platform and language, which forms strong foundation of integration of existing information resources. The core of CORBA is ORB which provides the interoperability of CORBA objects and interworking between CORBA objects and non-CORBA objects. Delphi is the best visual Object-Oriented programming tool for CORBA and it integrated Inprise VisiBroker to realize CORBA. Using Delphi and VisiBroker ,the CORBA application can realize the CORBA objects, load balance and capability of fault-tolerance easily. It apparently increases developers' effectivity. This paper discusses the core of CORBA –ORB and POA realized by the latest version from the CORBA object mode l. After deeply researching the theory and implementation of CORBA in delphi , the paper realize a multi layer distributed CORBA application system produced by Delphi visibroker . The system implements the CORBA object to make many clients operate the database of hosts in the network. Finally, the fault-tolerance of CORBA objects in Delphi is discussed deeply and the important factors to influence CORBA's performance are introduced. in detail.