JAVA外文翻译.doc

英文原文:The Java programming language and platform have emerged as major technologies for performing e-business functions. Java programming standards have enabled portability of applications and the reuse of application components across computing platforms. Sun Microsystems Java Community Process continues to be a strong base for the growth of the Java infrastructure and language standards. This growth of open standards creates new opportunities for designers and developers of applications and services .Applications of Java Java uses many familiar programming concepts and constructs and allows portability by providing a common interface through an external Java Virtual Machine (JVM). A virtual machine is a self-contained operating environment, created by a software layer that behaves as if it were a separate computer. Benefits of creating virtual machines include better exploitation of powerful computing resources and isolation of applications to prevent cross-corruption and improve security.The JVM allows computing devices with limited processors or memory to handle more advanced applications by calling up software instructions inside the JVM to perform most of the work. This also reduces the size and complexity of Java applications because many of the core functions and processing instructions were built into the JVM. As a result, software developers no longer need to re-create the same application for every operating system. Java also provides security by instructing the application to interact with the virtual machine, which served as a barrier between applications and the core system, effectively protecting systems from malicious code.Among other things, Java is tailor-made for the growing Internet because it makes it easy to develop new, dynamic applications that could make the most of the Internets power and capabilities. Java is now an open standard, meaning that no single entity controls its development and the tools for writing programs in the language are available to everyone. The power of open standards like Java is the ability to break down barriers and speed up progress.Today, you can find Java technology in networks and devices that range from the Internet and scientific supercomputers to laptops and cell phones, from Wall Street market simulators to home game players and credit cards. There are over 3 million Java developers and now there are several versions of the code. Most large corporations have in-house Java developers. In addition, the majority of key software vendors use Java in their commercial applications (Lazaridis, 2003).Applications Java on the World Wide Web Java has found a place on some of the most popular websites in the world and the uses of Java continues to grow. Java applications not only provide unique user interfaces, they also help to power the backend of websites. Everybody is probably familiar with eBay and Amazon have been Java pioneers on the World Wide Web.eBay Founded in 1995, eBay enables e-commerce on a local, national and international basis with an array of Web sites.You can find it on eBay, even if you didnt know it existed. On a typical day, more than 100 million items are listed on eBay in tens of thousands of categories. on eBay; the worlds largest online marketplace.eBay uses Java almost everywhere. To address some security issues, eBay chose Sun Microsystems Java System Identity Manager as the platform for revamping its identity management system. The task at hand was to provide identity management for more than 12,000 eBay employees and contractors.Now more than a thousand eBay software developers work daily with Java applications. Javas inherent portability allows eBay to move to new hardware to take advantage of new technology, packaging, or pricing, without having to rewrite Java code.Amazon A has created a Web Service application that enables users to browse their product catalog and place orders. A uses a Java application that searches the Amazon catalog for books whose subject matches a user-selected topic. The application displays ten books that match the chosen topic, and shows the author name, book title, list price, Amazon discount price, and the cover icon. The user may optionally view one review per displayed title and make a buying decision.Java in Data Warehousing & Mining Although many companies currently benefit from data warehousing to support corporate decision making, new business intelligence approaches continue to emerge that can be powered by Java technology. Applications such as data warehousing, data mining, Enterprise Information Portals and Knowledge Management Systems are able to provide insight into customer retention, purchasing patterns, and even future buying behavior.These applications can not only tell what has happened but why and what may happen given certain business conditions; As a result of this information growth, people at all levels inside the enterprise, as well as suppliers, customers, and others in the value chain, are clamoring for subsets of the vast stores of information to help them make business decisions. While collecting and storing vast amounts of data is one thing, utilizing and deploying that data throughout the organization is another.The technical challenges inherent in integrating disparate data formats, platforms, and applications are significant. However, emerging standards such as the Application Programming Interfaces that comprise the Java platform, as well as Extendable Markup Language technologies can facilitate the interchange of data and the development of next generation data warehousing and business intelligence applications. While Java technology has been used extensively for client side access and to presentation layer challenges, it is rapidly emerging as a significant tool for developing scaleable server side programs. The Java2 Platform, Enterprise Edition (J2EE) provides the object, transaction, and security support for building such systems.Metadata Issues One of the key issues that business intelligence developers must solve is that of incompatible metadata formats. Metadata can be defined as information about data or simply data about data. In practice, metadata is what most tools, databases, applications, and other information processes use to define, relate, and manipulate data objects within their own environments. It defines the structure and meaning of data objects managed by an application so that the application knows how to process requests or jobs involving those data objects. Developers can use this schema to create views for users. Also, users can browse the schema to better understand the structure and function of the database tables before launching a query.To address the metadata issue, a group of companies have joined to develop the Java Metadata Interface (JMI) API. The JMI API permits the access and manipulation of metadata in Java with standard metadata services. JMI is based on the Meta Object Facility (MOF) specification from the Object Management Group (OMG). The MOF provides a model and a set of interfaces for the creation, storage, access, Metamodel and metadata interchange is done via XML and uses the XML Metadata Interchange (XMI) specification, also from the OMG. JMI leverages Java technology to create an end-to-end data warehousing and business intelligence solutions framework.Enterprise JavaBeans A key tool provided by J2EE is Enterprise JavaBeans (EJB), an architecture for the development of component-based distributed business applications. Applications written using the EJB architecture are scalable, transactional, secure, and multi-user aware. These applications may be written once and then deployed on any server platform that supports J2EE. The EJB architecture makes it easy for developers to write components, since they do not need to understand or deal with complex, system-level details such as thread management, resource pooling, and transaction and security management. This allows for role-based development where component assemblers, platform providers and application assemblers can focus on their area of responsibility further simplifying application development.Data Storage & Access Data stored in existing applications can be accessed with specialized connectors. Integration and interoperability of these data sources is further enabled by the metadata repository that contains metamodels of the data contained in the sources, which then can be accessed and interchanged uniformly via the JMI API. These metamodels capture the essential structure and semantics of business components, allowing them to be accessed and queried via the JMI API or to be interchanged via XML. Through all of these processes, the J2EE infrastructure ensures the security and integrity of the data through transaction management and propagation and the underlying security architecture.To consolidate historical information for analysis of sales and marketing trends, a data warehouse is often the best solution. In this example, data can be extracted from the operational systems with a variety of Extract, Transform and Load tools (ETL). The metamodels allow EJBs designed for filtering, transformation, and consolidation of data to operate uniformly on data from diverse data sources as the bean is able to query the metamodel to identify and extract the pertinent fields. Queries and reports can be run against the data warehouse that contains information from numerous sources in a consistent, enterprise-wide fashion through the use of the JMI API.Java in Industrial Settings Many people know Java only as a tool on the World Wide Web that enables sites to perform some of their fancier functions such as interactivity and animation. However, the actual uses for Java are much more widespread. Since Java is an object-oriented language, the time needed for application development is minimal. In addition, Javas automatic memory management and lack of pointers remove some leading causes of programming errors. Most importantly, application developers do not need to create different versions of the software for different platforms. The advantages available through Java have even found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.Benefits of Java The benefits of Java translate across many industries, and some are specific to the control and automation environment. Javas ability to run on any platform enables the organization to make use of the existing equipment while enhancing the application.Integration With few exceptions, applications running on the factory floor were never intended to exchange information with systems in the executive office, but managers have recently discovered the need for that type of information. Before Java, that often meant bringing together data from systems written on different platforms in different languages at different times. Integration was usually done on a piecemeal basis, once it worked, was unique to the two applications it was tying together. Additional integration required developing a brand new system from scratch, raising the cost of integration.Scalability Another benefit of Java in the industrial environment is its scalability. Even when internal compatibility is not an issue, companies often face difficulties when suppliers with whom they share information have incompatible systems. This becomes more of a problem as supply-chain management takes on a more critical role which requires manufacturers to interact more with offshore suppliers and clients. The greatest efficiency comes when all systems can communicate with each other and share information seamlessly. Since Java is so ubiquitous, it often solves these problems.Dynamic Web Page Development Java has been used by both large and small organizations for a wide variety of applications beyond consumer oriented websites. Sandia, a multiprogram laboratory of the U.S. Department of Energys National Nuclear Security Administration, has developed a unique Java application. The lab was tasked with developing an enterprise-wide inventory tracking and equipment maintenance system that provides dynamic Web pages. Conclusion Open standards have driven the e-business revolution. As e-business continues to develop, various computing technologies help to drive its evolution. The Java programming language and platform have emerged as major technologies for performing e-business functions. the time needed for application development is minimal. Java also encourages good software engineering practices with clear separation of interfaces and implementations as well as easy exception handling. Javas automatic memory management and lack of pointers remove some leading causes of programming errors. The advantages available through Java have also found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.中文翻译:Java编程语言和Java平台，已成为主要的实现电子商务功能的技术。Java编程的标准，是便携性的应用和再利用的应用组件的计算平台。Sun Microsystems的Java程序社区仍然是增长Java基础设施和语言标准一个强有力的基础。这一增长为开放标准创造了新的设计机会和开发的应用服务程序。 Java的应用 Java使用许多熟悉的编程概念和结构，通过外部Java虚拟机(JVM)为便携性提供了一个共同的接口。虚拟机是一个自成一体的运行环境，给人的感觉就好像它是一个单独的计算机。创造虚拟机的好处包括更好地利用强大的计算资源和隔离的应用程序，以防止交叉和提高安全性。 JVM将通过调用软件指示内的JVM执行的大部分工作，允许计算设备有限处理器或记忆体用来处理更高级的应用程序，因为内置的虚拟机的许多核心职能和处理指示，这也减小了Java应用程序的规模和复杂性。其结果是，软件开发人员不需要在每个操作系统上重新建立相同的应用程序。Java也提供了用于安全的指示互动应用的虚拟机，作为应用程序之间的障碍和核心制度，有效地保护系统不受恶意代码的影响。除此之外，Java是专门应用于日益增长的互联网开发，因为它容易开发新的、动态的应用，可以充分发挥大多数互联网的潜能。Java现在是一个开放的标准，也就是说，没有一个单一的实体控制其编程的语言的发展，人人都可获得。Java开放标准能够打破开放源代码的障碍，加快了发展速度。今天，你可以在网络和因特网设备中可以找到Java技术的应用，从互联网和科学超级计算机到笔记本电脑和手机以及来自华尔街的市场模拟器首页游戏卡和信用卡。有超过300万Java开发者，现在有多个版本的代码，多数大型企业在内部都有Java开发人员。此外，大多数的重要软件供应商在商业应用中使用Java。应用 JAVA的万维网Java在世界上一些最流行的网站上找到一片空间并且Java的使用空间会继续增长。Java应用程序不仅提供了独特的用户界面，它们还有助于控制网站的后台。在万维网上，每个人都可能eBay和亚马逊一样成为Java领头人。易趣成立于1995年，易趣在地方、国家和国际的电子商务基础上提供了一系列的网站，你可以在eBay上找到它，即使你不知道它的存在。甚至有时候一天当中，在eBay上列出了数以万计类别的超过100万件的物品。易趣是世界上最大的在线市场。 易趣无处不在使用JAVA。为了解决一些安全问题，易趣选择了Sun Microsystems的Java系统身份管理平台，改进其身份管理系统。易趣手头的任务是为超过12000名员工和承包商提供身份管理。 易趣现在拥有了一千多易趣软件开发商日常工作使用Java应用程序。 Java固有的便携性使得易趣转移到新的硬件以利用新技术包装，或更改价格，而不必重写Java代码。 亚马逊 A创建了一个Web服务应用程序，使用户可以浏览他们的产品目录和订货。 A使用Java应用程序，搜索亚马逊图书目录主题来匹配用户选择的主题。应用程序显示10个条目来匹配选择的图书主题，显示了作者姓名、书名、定价、亚马逊的折扣价格以及覆盖图标。用户可以选择性地查看每一个显示标题，并作出购买决策。 数据仓库中的Java与挖掘 虽然许多公司目前受益于数据仓库，以支持企业决策，不断涌现采用Java技术控制新的商务智能的方法。应用程序如数据仓库，数据挖掘，企业信息门户和知识管理系统能够提供深入了解客户的保留，购买模式，甚至未来的购买行为。 这些应用不仅可以知道发生了什么事情，并且还能知道为什么和为可能会发生某些业务提供条件。由于这种信息的增长，在各级人民内部的企业、供应商，客户和其他价值链中，非常渴望知道广大商店的信息以帮助他们作出商业决策。虽然收集和储存大量的数据是一回事，而利用和部署数据在整个组织是另一回事。 该技术的主要挑战是整合不同的数据格式、平台和应用程序。然而，新兴的标准，比如应用编程接口，包括Java平台以及可扩展标记语言技术，可以便利交换数据和开发下一代数据仓库和商业智能应用。虽然Java技术已被广泛用于客户端访问，但是它正在迅速成为挑战表示层的一个重要工具以及发展中国家可伸缩的服务器端程序。在Java2平台企业版(J2EE)中提供了对象、交易和安全支持建立这种系统。元数据问题 这里的关键问题之一是商业智能开发必须解决不相容的数据格式。元数据可以被界定为信息数据或简单的“关于数据的数据”。在实践中，元数据是大多数工具、数据库、应用程序和其他信息处理使用的定义，在他们自己的环境中涉及和操纵数据对象。它定义数据结构和管理数据对象的申请，以便知道如何达到应用程序要求或处理这些数据对象。开发者可以使用这个架构为用户提供意见。另外，用户可以浏览架构，以更好地理解结构和功能数据库表的查询。 为了解决元数据问题，一批公司加入到Java元数据接口的API的开发。在JIM的API中提供了允许访问和操纵数据的Java标准的元数据服务。JIM是基于元对象设施规范的对象管理组。元模型和元数据交换是通过XML和使用XML元数据交换(XM