《翻译文献-java企业版平台（jee）的企业级javabean（ejb）构件体系结构》由会员分享，可在线阅读，更多相关《翻译文献-java企业版平台（jee）的企业级javabean（ejb）构件体系结构（20页珍藏版）》请在金锄头文库上搜索。
1、大连交通大学2016届本科生毕业设计（论文）外文翻译外文原文PART ONE OverviewIn Part I, we introduce the server-side development platform that is the Java 2 Platform, Enterprise Edition (J2EE), of which the Enterprise JavaBeans (EJB) component architecture is a vital piece. J2EE is a conglomeration of concepts, programming stand
2、ards, and innovationsall written in the Java programming language. With J2EE, you can rapidly construct distributed, scalable, reliable, and portable secure server-side deployments.Chapter 1 begins by exploring the need for a server-side development platform such as J2EE. Youll see the rich needs of
3、 server-side computing, such as scalability, high availability, resource management, and security. Youll also see the need for a rapid application development component architecture such as EJB and COM+. Well wrap up by surveying Sun Microsystems J2EE, a complete server-side development platform.Cha
4、pter 2 moves on to the Enterprise JavaBeans component model. Well take a look at how EJB empowers heterogeneous vendors to collaborate to solve a business problem, and well study the roles of each party in an EJB deployment. Well also look at the different functional software modules in an EJB deplo
5、yment and how they relate.Server-side ComponentArchitecturesEnterprise JavaBeans (EJB) is a server-side component architecture that enables and simplifies the process of building enterprise-class distributed object applications in Java. By using EJB, you can write scalable, reliable, and secure appl
6、ications without writing your own complex distributed object framework. EJB is about rapid application development for the server side; you can quickly and easily construct server-side components in Java by leveraging a prewritten distributed infrastructure provided by the industry. EJB is designed
7、to support application portability and reusability across any vendors enterprise middleware services. If you are new to enterprise computing, these concepts will be made very clear shortly. EJB is a complicated subject and thus deserves a thorough explanation. In this chapter, well discusses the mai
8、n concepts surrounding Enterprise JavaBeans. This starts with a discussion about whats involved in writing enterprise software and why a prepackaged distributed object architecture such as Enterprise JavaBeans simplifies your life. From this discussion, well have a greater insight into why a server-
9、side component architecture makes sense, as well as a feature list of what wed like to see when we choose an architecture for developing server-side distributed object applications.Well then examine several endeavors by the industry to address these enterprise needs. The highlight of this discussion
10、as well as this bookis Suns Java 2 Platform, Enterprise Edition (J2EE). J2EE is a collection of enterprise technologies, of which EJB is an integral part. By understanding and using J2EE properly, you can build portable, object-oriented, enterprise-class applications in Java.The Need for a Server-Si
11、de Component ArchitectureTo understand the value EJB brings to the table, we first must examine the needs that developers commonly have when authoring and deploying components in a server-side environment. As we uncover the issues surrounding server-side development, well begin to see the need for a
12、 standardized architecture such as EJB.Software ComponentsWe begin our discussion with a look at software components. A software component is code that implements a set of well-defined interfaces. It is a manageable, discrete chunk of logic. Components are not entire applicationsthey cannot run alon
13、e. Rather, they can be used as puzzle pieces to solve some larger problem.The idea of software components is very powerful. A company can purchase a well-defined module that solves a problem and combine it with other components to solve larger problems. For example, consider a software component tha
14、t computes the price of goods. Well call this a pricing component. You hand the pricing component information about a set of products, and it figures out the total price of the order.The pricing problem can get quite hairy. For example, lets assume were ordering computer parts, such as memory and ha
15、rd drives. The pricing component figures out the correct price based on a set of pricing rules such as:Base prices of a single memory upgrade or a single hard diskQuantity discounts that a customer receives for ordering more than 10 memory modulesBundling discounts that the customer receives for ord
16、ering both memory and a hard diskPreferred customer discounts that you can give to big-name customersLocale discounts depending on where the customer livesOverhead costs such as shipping and taxesThese pricing rules are in no way unique to ordering computer parts. Other industries, such as health care, appliances, airline tickets, and others need the same pricing functionality. Obviously, it would be a huge waste
