| In the last few years, the distributed processing technique combined with Object-Oriented technical becomes mainstream in the computer software field.The popular distributed technique includes:The COM/DCOM put forward by Microsoft ;The technique of CORBA put forward by OMG ;The technique of EJB put forward by Sun ; Among them ,the COM/DCOM is the core of the operating system of Microsoft, the Micros oft declares that the technique can be used on other operating systems except Windows, but in fact,making COM/DCOM running on Unix is a difficult thing; The EJB is based on Java ,and the target of Sun corporation is to implement a kind of components technique of the platform independence. But Java itself does not becomes good enough, so EJB technique still is not the ageing fully. The CORBA is opened and has good expansibility. In recent years, CORBA absorbs many good features from other middleware techniques . At the same time it absorbs the latest techniques such as Java, UML, XML, components technique and mobile agency,etc.The technique of CORBA makes the standard first , and the product behind, this is quite different from other middleware products. Now the technique of CORBA is used in bank, telecommunication, insurance, electric power and electronic commerce field etc. But in our country ,the research in CORBA gives priority to application , and little in realization ; As some specialist's said, the domestic software territory should pay more attention to system software research, so we can overtake the international level ;The design of CORBA platform is exactly the design of the system software, so this paper probes into the implement of CORBA platform. This paper's main research work is divided into two parts.The first part is a CORBA core module research and realization, this part is the result of my tutor's senior postgraduate's hard work.The author proceeds to perfect this part and tidyed it up.The second part is four kinds of CORBA Service's research and realization.This part is the main part of the whole paper.These four kinds of service are Naming Service,Event Service,Transaction Service and ConcurrencyControl Service respectively.In this part, the author offers basic principles and interface of these Service first, then give a realization .1.CORBA core module research and realization The realization of CORBA is a complex project.The CORBA core module discussed in this paper is a mimimum CORBA keeping the core function of CORBA.It include two main module:orb module and poa module.Orb module is constituted by seven packages :orb package,is the core package of the whole system,responsible for implementing the orb interface and mamaging other parts of the system;Thread package,responsible for starting listening thread which listen the client's request after orb started and handling these requests;ior package,responsible for encapsulation of IOR(interoperable object reference)and it's operation;giop package,responsible for establishing a client and server side of a communications channel;iiop package and protocols package which inherites from iiop package,responsible for establishing a communication channel abiding by GIOP protocol between two sides;cdr package,responsible for coding and decoding the octet streams.In this part,in addition to giving the static structure,through action and sequence graph,the whole dynamatic process of the request being delivered in Client side is analysed. In poa module,firstly presents it's static structure,then analyses the relationship between it and orb module and the process of request being handled in Server side.2.CORBA service research and implementing Primarily taking about four services' research and implementing.(1)The design and implementing of Naming Service In chapt 3,the author discussed the implementing of Naming Service which is responsible for the binding and resolving the distributed object name to object reference.The autor implements NamingContectExt and BindingIterator interface according OMG specification.In a...
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