ejb基础与会话bean (java类论文外文翻译).doc

EJB基础与会话Bean (java类论文外文翻译)

中文译文：

   EJB基础与会话Bean

到目前为止，我们已经讨论了用户界面，业务逻辑和开发Java EE应用程序的数据库连接方面的问题。讨论的主要机制是为指出从JSP和Servlet代码被访问的JavaBeans所表达业务逻辑。Java EE有一个表达了一个应用程序的业务逻辑和数据库访问使用一个JavaBeans一样强大的概念专用设施。该设施是企业JavaBeans，EJB的已很少被认知。

在这一章中，我们将开始探讨EJB，这是一个对Java EE平台很重要的能力世界。 EJB的开发和部署提供关键任务企业应用的基础设施。我们首先看一些EJB的基础，然后集中在一个类型的EJB：会话bean。

在这一章中，你将学习以下内容..

外文文献：　

EJB Fundamentals and Session Beans

So far, we’ve discussed the user interface, business logic, and database connection aspects of developing Java EE applications. The primary mechanism discussed to this point for expressing business logic has been JavaBeans accessed from JSP and Servlet code. Java EE has a powerful facility dedicated to expressing the business logic of an application and for accessing a database using a JavaBeans-like concept. That facility is Enterprise JavaBeans, known as EJBs for short.

In this chapter, we’ll begin exploring the world of EJBs, which is a very important capability of the Java EE platform. EJBs provide infrastructure for developing and deploying mission-critical,enterprise applications. We’ll first look at some EJB fundamentals, and then focus on one type of EJB: the session bean.

In this chapter, you will learn the following:

• The benefits of using EJBs

• The three kinds of EJBs: session, entity, and mess