Orb Rmi-iiop-based Design And Realization

RMI is used as distributed service framework in Java language. With RMI you can write distributed program in Java. The strongpoint of RMI is its easy definition of interfaces, without complicated syntax rule with IDL. However, RMI lacks the interoperability with other programming language, since it communicates over JRMP which is not standard communication protocol. So it is impossible to communicate with CORBA objects.HOP is designed to support CORBA communication protocol. CORBA is a distributed object infrastructure announced by OMG. In CORBA2.0, a abstract protocol for universal ORB interoperation called GIOP is introduced. HOP is a implementation of GIOP using TCP/IP. All present ORBs have ability to communicate over HOP.Previously Java programmers had to choose between RMI and CORBA/IIOP for distributed programming solutions. By adhering to a few restrictions, RMI objects can use the HOP protocol, and communicate with CORBA objects. This solution is known as RMI-IIOP. RMI-IIOP combines RMI-style ease of use with CORBA cross-language interoperability.The main goal of thesis is to design and implement RMI-IIOP communication based on ORB. As one part of J2EE application server EJB, it provides EJB the ability of mutual-communication with CORBA clients and servers. Therefore, EJB can be applied in large-scale and heterogeneous network of enterprises, without no unnecessary limitations of system architecture.The thesis makes detailed description about the design idea and implementation of RMI-IIOP. What the thesis has tried to expound first is the infrastructure and specification of RMI-IIOP. The design and implementation of each module is described in each chapter. The content in the third chapter is the realization of RMI-IIOP's complier, including compiler's function as well as that of stub and skeleton .The design of interface in RMI-IIOP is written up in Chapter Four, especially about each class or interface of PortablityAPI in the specification. In Chapter Five,it is concerned on user-defined stream classes. Although they are not in specification, they are implemented in this total design in need of programming. They are designed to provide easy-use methods, thus make total architecture plainer. At last, the author presents some consideration about unfulfilment for the sake of further improvement.