Ejb Distributed Object Technology And Design, Online Teaching System

To make the education more popular and more powerful, many countries have taken the research and development of e-learning system as their basic strategy. There is a huge educational market for e-learning systems. A well-designed such distributed system should be easily extendable and portable. Meanwhile, it must have a good performance in dealing with the limit of centralized system and low network bandwidth. On the other hand, the infrastructure and the supporting environment of Distributed Object Technology have been developed rapidly. It ensures that the Distributed Object Technology performs well in improving the ability of information processing, collaboration among heterogeneous systems, reliability and scalability. According to the above, the most popular technologies of Distributed Object Technology are discussed in this paper. Moreover, the J2EE EJB Distributed Object Technology is analyzed in detail. The paper specifies the general requirements and the architecture needed to implement an e-learning system based on J2EE EJB. The architecture gives a satisfactory solution for e-learning systems which require good scalability and portability. It also eliminates the performance bottleneck related to bandwidth limitation and improves computability. The organization of this paper is as follow. At the beginning, the background of the task application and basic technology involved in are introduced. Next the underlying principles of three typical kinds of Distributed Object Technology, DCOM, CORBA and EJB are studied. The similarities and differences of these three technologies are also summarized. Then the J2EE platform and EJB Distributed Object Technology are discussed in detail. The research includes anatomizing their infrastructures, components, designing issues and deployment requirements. Fourthly, the status quo and defects of the existing e-learning systems are contrasted. Based on the analysis, the functional description and the requirement of a new e-learning system are provided. Finally, the implementation issues such as architecture design based on Struts, database design and EJB component design of e-learning systems equipped with J2EE EJB Distributed Object Technology is investigated. Some program codes are attached for demonstration.