EJB在企业级电子商务开发中的应用

Application of EJB to enterprise E-commerce

简要介绍了EJB的概念和特性,举例说明如何利用本地接口和本地Home接口来防止本地客户端访问EJB组件时产生附加的网络通信量.接下来对新的CMP组件模型进行了详尽阐述,通过实例解释了持久性管理器在提高系统可移植性方面发挥的关键作用.最后介绍了新的EJB规范中引入的消息驱动Bean,比较了它与会话和实体Bean之间的区别,并从实践角度给出了利用消息驱动Bean和消息传递集群构造基于非耦合多层次体系结构的企业级电子商务系统的方法.

The notion and character of EJB are introduced firstly. Then an example is given to explain the way that preventing the local access to EJB component from making additional network flux by using local interface and local home interface. Following the example, new CMP component model is expounded in detail. An instance was furnished to show the key role played by the persistence-manager in the aspect of improving system portability. The author discusses MessageDrivenBean introduced by new EJB criterion in the last part of this paper, and compared it with the other beans, such as session bean and entity bean. Finally, a way is put forward from the viewpoint of practice that used MessageDrivenBean and Message-Passing-Cluster to construct enterprise e-commerce system based on non-coupling multi-layer architecture.