软件工程本科毕业外文文献翻译资料

软件工程本科毕业外文文献翻译

学校代码：

10128

本科毕业设计外文文献翻译

二〇一五年一月

The Test Library Management System of

Framework Based on SSH

The application system features in small or medium-

sized enterprise lie in the greater flexibility and safety high performance-

price ratio. Traditional J2EE framework can not adapt to these needs, but the system a pplication based on SSH(Struts+Spring+Hibernate) technology can better satisfy such needs. This paper analyses some integration theory and key technologies about SSH, and according to the integration constructs a lightweight WEB framework, which has integrated the three kinds of technology ,forming the lightweight WEB framework bas ed on SSH and gaining good effects in practical applications.

Introduction

Generally the J2EE platform[27] used in large enterprise applications, can well s olve the application of reliability, safety and stability, but its weakness is the price hig h and the constructing cycle is long. Corresponding to the small or medium enterprise applications, the replace approach is the system framework of lightweight WEB, inclu ding the more commonly used methods which are based on the Struts and Hibernate. With the wide application of Spring, the three technology combination may be a bette r choice as a lightweight WEB framework. It uses layered structure and provides a go od integrated framework for Web applications at all levels in minimizing the Interlaye r coupling and increasing the efficiency of development. This framework can solve a l ot of problems, with good maintainability and scalability. It can solve the separation o f user interface and business logic separation, the separation of business logic and data base operation and the correct procedure control logic, etc. This paper studies the tech nology and principle of Struts and Spring and Hibernate, presenting a proved lightwei ght WEB application framework for enterprise.

Hierarchical Web Mechanism

Hierarchical Web framework including the user presentation layer, business logi clayer, data persistence layer ,expansion layer etc, each layer for different function, re spectively to finish the whole application. The whole system are divided into different

logic module with relatively independent and mutual, and each module can be imple mented according to different design. It can realize the system parallel development, r apid integration, good maintainability, scalability.

Struts MVC Framework

To ensure the reuse and efficiency of development process, adopting J2EE techn ology to build the Web application must select a system framework which has a good performance . Only in this way can we ensure not wasting lots of time because of adju sting configuration and achieve application development efficiently and quickly. So, p rogrammers in the course of practice got some successful development pattern which proved practical, such as MVC and O/R mapping, etc; many technologies, including S truts and Hibernate frameworks, realized these pattern. However, Struts framework on ly settled the separation problem between view layer and business logic layer, control layer, did not provide a flexible support for complex data saving process. On the contr ary, Hibernate framework offered the powerful and flexible support for complex data saving process. Therefore, how to integrate two frameworks and get a flexible, low-coupling solutions project which is easy to maintain for information system, is a resea rch task which the engineering staff is studying constantly.

Model-View-

Controller (MVC) is a popular design pattern. It divides the interactive system in three components and each of them specializes in one task. The model contains the applica tion data and manages the core functionality. The visual display of the model and the f eedback to the users are managed by the view. The controller not only interprets the in puts from the user, but also dominates the model and the view to change appropriately . MVC separates the system functionality from the system interface so as to enhance t he system scalability and maintainability. Struts is a typical MVC frame[32], and it also contains the three aforementioned components. The model level is composed of J avaBean and EJB components. The controller is realized by action and ActionServlet, and the view layer consists of JSP files. The central controller controls the action exec ution that receives a request and redirects this request to the appropriate module contr oller. Subsequently, the module controller processes the request and returns results to

the central controller using a JavaBean object, which stores any object to be presented in the view layer by including an indication to module views that must be presented. The central controller redirects the returned JavaBean object to the main view that dis plays its information.

Spring Framework technology

Spring is a lightweight J2EE application development framework, which uses the model of Inversion of Control(IoC) to separate the actual application from the Config uration and dependent regulations of the application. Committed to J2EE application a t all levels of the solution, Spring is not attempting to replace the existing framework, but rather “welding” the object of J2EE application at all levels together through the P OJO management. In addition, developers are free to choose Spring framework for so me or all, since Spring modules are not totally dependent.

As a major business-

level detail, Spring employs the idea of delay injection to assemble code for the sake o f improving the scalability and flexibility of built systems. Thus, the systems achieve a centralized business processing and reduction of code reuse through the Spring AOP module.

Hibernate Persistent Framework

Hibernate is a kind of open source framework with DAO design patterns to achie ve mapping(O/R Mapping) between object and relational database.

During the Web system development, the tradition approach directly interacts wi th the database by JDBC .However, this method has not only heavy workload but also complex SQL codes of JDBC which need to revise because the business logic sli ghtly changes. So, whatever development or maintain system are inconvenient. Consi dering the large difference between the object-

oriented relation of java and the structure of relational database, it is necessary to intro duce a direct mapping mechanism between the object and database, which this kind of mapping should use configuration files as soon as possibility, so that mapping files w ill need modifying rather than java source codes when the business logic changes in th

e future. Therefore, O/R mapping pattern emerges, which hibernate is one o

f the most outstandin

g realization of architecture.

It encapsulates JDBC with lightweight , making Java programmer operate a relati onal database with the object oriented programming thinking. It is a a implementation technology in the lasting layer. Compared to other lasting layer technology such as JD BC, EJB, JDO, Hibernate is easy to grasp and more in line with the object-

oriented programming thinking. Hibernate own a query language (HQL), which is full y object-oriented. The basic structure in its application as shown in figure6.1.

Hibernate is a data persistence framework, and the core technology is the object / relational database mapping(ORM). Hibernate is generally considered as a bridge bet ween Java applications and the relational database, owing to providing durable data se rvices for applications and allowing developers to use an object-

oriented approach to the management and manipulation of relational database. Further more, it furnishes an object-oriented query language-HQL.

Responsible for the mapping between the major categories of Java and the relatio nal database, Hibernate is essentially a middle ware providing database services. It su pplies durable data services for applications by utilizing databases and several profiles , such as hibernate properties and XML Mapping etc..

Web services technologies

The introduction of annotations into Java EE 5 makes it simple to create sophisticated Web service endpoints and clients with less code and a shorter learning curve than was possible with earlier Java EE versions. Annotations — first introduced in Java SE 5 — are modifiers you can add to your code as metadata. They don't affect program semantics directly, but the compiler, development tools, and runtime libraries can process them to produce additional Java language source files, XML documents, or other artifacts and behavior that augment the code containing the annotations (see Resources). Later in the article, you'll see how you can easily turn a regular Java class into a Web service by adding simple annotations.

Web application technologies

Java EE 5 welcomes two major pieces of front-end technology — JSF and JSTL — into the specification to join the existing JavaServer Pages and Servlet specifications. JSF is a set of APIs that enable a component-based approach to user-interface development. JSTL is a set of tag libraries that support embedding procedural logic, access to JavaBeans, SQL commands, localized formatting instructions, and XML processing in JSPs. The most recent releases of JSF, JSTL, and JSP support a unified expression language (EL) that allows these technologies to integrate more easily (see Resources).

The cornerstone of Web services support in Java EE 5 is JAX-WS 2.0, which is a follow-on to JAX-RPC 1.1. Both of these technologies let you create RESTful and SOAP-based Web services without dealing directly with the tedium of XML processing and data binding inherent to Web services. Developers are free to continue using JAX-RPC (which is still required of Java EE 5 containers), but migrating to JAX-WS is strongly recommended. Newcomers to Java Web services might as well skip JAX-RPC and head right for JAX-WS. That said, it's good to know that both of them support SOAP 1.1 over HTTP 1.1 and so are fully compatible: a JAX-WS Web services client can access a JAX-RPC Web services endpoint, and vice versa.

The advantages of JAX-WS over JAX-RPC are compelling. JAX-WS:

?Supports the SOAP 1.2 standard (in addition to SOAP 1.1).

?Supports XML over HTTP. You can bypass SOAP if you wish. (See the article "Use XML directly over HTTP for Web services (where appropriate)"

for more information.)

?Uses the Java Architecture for XML Binding (JAXB) for its data-mapping model. JAXB has complete support for XML schema and better

performance (more on that in a moment).

?Introduces a dynamic programming model for both server and client.

The client model supports both a message-oriented and an asynchronous approach.

?Supports Message Transmission Optimization Mechanism (MTOM), a W3C recommendation for optimizing the transmission and format of a SOAP message.

?Upgrades Web services interoperability (WS-I) support. (It supports Basic Profile 1.1; JAX-WS supports only Basic Profile 1.0.)

?Upgrades SOAP attachment support. (It uses the SOAP with Attachments API for Java [SAAJ] 1.3; JAX-WS supports only SAAJ 1.2.)

?You can learn more about the differences by reading the article "JAX-RPC versus JAX-WS."

The wsimport tool in JAX-WS automatically handles many of the mundane details of Web service development and integrates easily into a build processes in a cross-platform manner, freeing you to focus on the application logic that implements or uses a service. It generates artifacts such as services, service endpoint interfaces (SEIs), asynchronous response code, exceptions based on WSDL faults, and Java classes bound to schema types by JAXB.

JAX-WS also enables high-performing Web services. See Resources for a link to an article ("Implementing High Performance Web Services Using JAX-WS 2.0") presenting a benchmark study of equivalent Web service implementations based on the new JAX-WS stack (which uses two other Web services features in Java EE 5 —JAXB and StAX) and a JAX-RPC stack available in J2EE 1.4. The study found 40% to 1000% performance increases with JAX-WS in various functional areas under different loads.

Conclusion

Each framework has its advantages and disadvantages .Lightweight J2EE struct ure integrates Struts and Hibernate and Spring technology, making full use the powerf ul data processing function of Struts and the management flexible of Spring and the m ature of Hibernate. According to the practice, putting forward an open-

source solutions suitable for small or medium-

sized enterprise application of. The application system based on this architecture tech nology development has interlayer loose coupling ,structure distinctly, short develop ment cycle, maintainability. In addition, combined with commercial project developm ent, the solution has achieved good effect. The lightweight framework makes the paral lel development and maintenance for commercial system convenience, and can push f orward become other industry business system development.

Through research and practice, we can easily find that Struts / Spring / Hiberna te framework utilizes Struts maturity in the presentation layer, flexibility of Spring bu siness management and convenience of Hibernate in the serialization layer, three kind s of framework integrated into a whole so that the development and maintenance beca me more convenient and handy. This kind of approach also will play a key role if appl ying other business system. Of course ,how to optimize system performance, enhance the user's access speed, improve security ability of system framework ,all of these wor ks, are need to do for author in the further.

基于SSH框架实现的试题库管理系统小型或者中型企业的应用系统具有非常好的灵活性、安全性以及高性价比，传统的J2EE架构满足不了这些需求，但是基于SSH框架实现的应用系统更好的满足了这样的需求，这篇文章分析了关于SSH的一体化理论和关键技术，通过这些集成形成了轻量级Web框架，在已经集成三种技术的基础上，伴随形成了基于SSH的轻量级Web 框架，并且在实际应用中有着重要作用。

简介

一般大型企业使用的是J2EE[27]平台，很好的解决了该应用的可靠性、安全性、稳定性，它的缺点是费用高、形成该系统的周期长，对于小型或者中型企业级应用，可以用轻量级Web代替系统框架，比如通用的Struts和Hibernate，随着Spring的广泛应用，轻量级Web框架开发的最好选择是Struts、Hibernate、Spring三者的相结合，因为它采用的是分层结构并且为Web应用程序在各层提供了一个框架的集成，这样不仅降低了层与层之间的耦合性，而且提高了开发效率。使用该框架可已经解决好多问题，具有可维护性和可扩展性，使得用户接口和业务逻辑层之间分离，业务逻辑层、数据库访问层、以及程序控制层的分离等。本文研究了Struts、Hibernate以及Spring的技术和使用原则，呈现出企业级轻量级Web应用框架开发的权威性。

网络分层机制

网络分层主要分为：视图层、控制层、数据库持久层、拓展层等，使用每一层不同的功能完成整个应用程序。整个系统划分成相互独立、相互依存的不同逻辑模块，根据具体设计调用不同的逻辑模块实现逐步实现该系统。同时实现系统并行开发、快速集成、可维护性、可扩展性。

Struts MVC 框架

为了确保高效率再次使用发展过程，采用J2EE技术去构建Web应用程序不许选择一个具有良好性能的框架，这使得我们没有花费大量时间去进行系统配置，而是去高效率、快速地实现系统开发，因此程序员拥有很好的发展平台并且开发经验有了提升，如：MVC、O/R映射等。运用包括Struts、Hibernate这些技术框架实现这种模式。然而，Struts解决的是视图层、业务逻辑层、控制层之间的分离，对于那些错综复杂的数据保存没有提供灵活的支持。相反，

Hibernate框架提供了强大且灵活的支持在保存错综复杂的数据时。因此工程人员正在研究使用框架并且灵活开发项目。

模型-视图-控制器，所谓的MVC是一种流行的设计模式。它把交互式系统中三种组成成分有一个明确的分工，各自负责自己的任务，MVC模型包含程序数据并且管理核心功能。模型和反馈给用户的可视化显示由视图层管理，控制层要负责解释来自用户的输入，属于主导地位，也会通过对控制层的操作来改变视图层。MVC从系统页面的分离来提高系统的可扩展性和可维护性。Struts 是典型的MVC框架，并且包含上述三层。模型级别由JavaBean和EJB组件构成，控制层通过ActionServlet的实现，视图层主要是JSP文件。ActionServlet执行JSP发出的请求，并重定向该请求到相应层进行继续处理。接着，控制层处理使用JavaBean对象，其存储任何视图层的数据通过来自页面的请求，并返回结果给控制层模块。控制层重定向返回的JavaBean对象，以显示其信息的主要内容。

Spring框架技术

Spring是轻量级应用开发技框架，使用来自配置文件和应用程序的控制分离中的实际应用，依据J2EE应用所有的解决方案，Spring不仅是取代现有的技术，更是组织对象进行POJO管理。此外，开发人员可以自由使用Spring框架的部分或者全部，源于Spring模块不完全依赖。

根据模块的业务描述，Spring采用加载延迟来提升代码的扩展性和内置系统的灵活性，该系统通过Spring Aop模块实现了集中业务处理，减少代码重用。

Hibernate的持久层框架

Hibernate持久层框架是一种用Dao设计模式实现对象和关系数据库之间映射的开源框架。随着网络系统的发展，传统的方法是使用JDBC直接相连，这种方式使得系统工作负荷大而且SQL语句错综复杂，一旦业务逻辑发生变化，SQL语句就得做相应的修改，这样给开发者和维护人员带来不便，考虑了Java 面向对象的关系与关系数据库存在很大差异性，介于对象和数据库之间引入配置文件进行之间映射，尽可能使用配置文件，只需要修改配置文件来代替Java 源代码当业务逻辑有所改变时。因此，关系映射的出现，是Hibernate最优秀的实现建筑之一。

Hibernate便捷的封装了JDBC，使得Java操作一个数据库与面向对象编程思维一致，它是一个持久层实现技术，比起其他持久层技术，如JDBC、EJB、JDO，Hibernate很容易掌握，更符合面向地向的编程思路，Hibernate特有的完全面向对象的查询语言（HQL）。

介于对象和关系数据库之间的映射是很关键的，Hibernate最本质的中间组件来提供服务，它通过利用数据库和多个配置文件，如Hibernate固有特性和XML映射等应用提供持久的数据服务.

WEB服务技术

在 Java EE 5 中引入了注解（annotation）特性，这简化了复杂 Web 服务端点和客户机的开发，与以前的 Java EE 版本相比，代码更少，学习过程更短了。注解（最早在 Java SE 5 中引入）是可以作为元数据添加到代码中的修饰性代码。它们并不直接影响程序的语义，但是编译器、开发工具和运行时库可以通过处理它们生成额外的 Java 语言源文件、XML 文档或其他工件和行为，这些对包含注解的程序起辅助作用（参见参考资料）。在本文后面，会看到如何通过添加简单的注解，将常规的 Java 类转换为 Web 服务。

Web 应用程序技术

除了现有的 JavaServer Pages 和 Servlet 规范，Java EE 5 引入了两种前端技术— JSF 和 JSTL。JSF 是一组 API，支持以基于组件的方式开发用户界面。JSTL 是一组标记库，支持在 JSP 中嵌入过程式逻辑、对 JavaBean 的访问方法、SQL 命令、本地化格式指令和 XML 处理。JSF、JSTL 和 JSP 的最新版本支持一种统一表达式语言（expression language，EL），这使这些技术更容易集成在一起（参见参考资料）。

Web 服务支持方面的飞跃

Java EE 5 中 Web 服务支持的基础是 JAX-WS 2.0，它是一种替代 JAX-RPC 1.1 的技术。这两种技术都支持创建 REST 风格和基于 SOAP 的 Web 服务，而不必直接处理 Web 服务固有的 XML 处理和数据绑定细节。开发人员可以继续使用 JAX-RPC（这仍然需要 Java EE 5 容器），但是强烈建议迁移到JAX-WS。刚开始学习 Java Web 服务的开发人员可以跳过 JAX-RPC，直接使用JAX-WS。它们都支持 SOAP 1.1 over HTTP 1.1，所以完全兼容：JAX-WS Web 服务客户机可以访问 JAX-RPC Web 服务端点，反之亦然。

与 JAX-RPC 相比，JAX-WS 有许多优点。JAX-WS：

?支持 SOAP 1.2 标准（以及 SOAP 1.1）。

支持 XML over HTTP。如果愿意，可以不使用 SOAP。（更多信息参见文章“Use XML directly over HTTP for Web services (where appropriate)”。）使用 Java Architecture for XML Binding（JAXB）作为数据映射模型。JAXB 完全支持 XML 模式，而且性能更好（更多信息见下文）。

?为客户机和服务器引入了一个动态编程模型。客户机模型支持面向消息方式和异步方式。

?支持 Message Transmission Optimization Mechanism（MTOM），这是一个用于优化 SOAP 消息传输和格式的 W3C 建议规范。

?升级了 Web services interoperability（WS-I）支持。（它支持Basic Profile 1.1；JAX-WS 只支持 Basic Profile 1.0。）

?升级了 SOAP 附件支持。（它支持 Attachments API for Java [SAAJ] 1.3：JAX-WS 只支持 SAAJ 1.2。）

通过阅读文章“Web 服务提示与技巧: JAX-RPC 与 JAX-WS 的比较”，可以进一步了解这些差异。

JAX-WS 中的 wsimport 工具自动地处理 Web 服务开发的许多细节，并以跨平台方式集成到构建过程中，这让开发人员可以将注意力集中于实现或使用服务的应用程序逻辑。它生成各种工件，包括服务、服务端点接口（SEI）、异步响应代码、基于 WSDL 错误的异常以及通过 JAXB 绑定到模式类型的 Java 类。

JAX-WS 还能够提高 Web 服务的性能。在文章“Implementing High Performance Web Services Using JAX-WS 2.0”（参见参考资料中的链接）中，对基于 JAX-WS 的 Web 服务实现（使用了 Java EE 5 中的另外两个 Web 服务特性— JAXB 和 StAX）和基于 J2EE 1.4 中的 JAX-RPC 的服务实现做了性能对比。这项研究发现在不同负载下 JAX-WS 在各个功能领域产生了 40% 到1000% 的性能改进。

结束语

每个框架都有其优点和缺点。轻量级J2EE集成了Struts、Hibernate、Spring技术，充分利用Struts的强大数据处理功能、管理灵活的Spring和成熟的Hibernate。根据常理，提出适合小型或中型的企业应用程序的开源解决方案，基于这种架构技术应用开发系统中间层低耦合，并且拥有结构清晰、开

发周期短、可维护性的特点。此外，结合商业项目的发展，用在这种方式解决意义重大。轻量级的框架，使得商业系统方便并行和维护，并且能推动其他商业系统的发展。

通过研究和实践，我们很容易发现的Struts+Spring+ Hibernate框架，Struts已有成熟的视图层，Spring有效管理和Hibernate持久化层操作的便捷性和灵活性，这三种框架的互相依存，这样的发展使得我们应用起来得心应手，这样的集成也将起到关键的作用，如果采用其他的开发模式。当然，如何改善系统性能、提高了用户的访问速度、提高了系统的框架的安全能力，剩下的这些工作有待于进一步研究。