KeyWords and Expressions

spawn[spɔ:n]  n.  (鱼等的)卵, (植物)菌丝, 产物  v.  产卵

originally['ə'ridʒənli] ad. 最初,原先

application['æpli'keiʃən]  n.  请求, 申请, 申请表, 应用, 应用程序, 应用软件

versatile['və:sətail]  a.  通用的, 万能的, 多才多艺的

proliferate[prəu'lifəreit] v.  增生扩散

corporation[kɔ:pə'reiʃən]  n.  [法律]社团, 法人; 公司, 企业, <美>有限公司

browser['brauzə]  n.  浏览器; 吃嫩叶的动物; 浏览书本的人

technician[tek'niʃən] n.  技术员, 技师

scarcely['skɛəsli] ad. 几乎不,简直没有

evolve[i'vɔlv]  v.  (使)发展, (使)进展, (使)进化

What is Java

1. Overview of Java

 Java is a high-level programming language developed by Sun Microsystems(Figure 7-1). Java was originally called OAK, and was designed for handheld devices and set-top boxes. OAK was unsuccessful so in1995 Sun changed the name to Java and modified the language to take advantage of the burgeoning World Wide Web.

                                                                   Figure 7-1 Java Logo

  Java is an object-oriented language (面向对象语言) similar to C++, but simplified to eliminate language features that cause common programming errors. Java source code files (files with a. java extension) are compiled into a format called bytecode (files with a. class extension), which can then be executed by a Java interpreter. Compiled Java code can run on most computers because Java interpreters and runtime environments, known as Java Virtual Machines (JVMs),exist for most operating systems, including UNIX, the Macintosh OS, and Windows. Bytecode can also be converted directly into machine language instructions by a just-in-time compiler (JIT). 

2. Character of Java

  Java is one of the hyped-up Internet software technologies that have spawned the World Wide Web, awful words like“intranet”, and those strange-looking addresses on business cards and TV commercials.[1] Originally known as a way to jazz up Web pages with graphicanimations —stock tickers that crawl across your screen, for example, anddancing icons—Java has quickly evolved into a whole lot more.[2] To Microsoft’sdismay, it is fast becoming what is known as a computing platform—a sturdy baseupon which programmers can build software applications.

  Java is making possible the rapid development of versatile programs for communicating and collaborating (协作) on the Internet. We’re not just talkingword processors and spreadsheets here, but also applications to handle sales,customer service, accounting, databases, and human resources—the meat and potatoes of corporate computing.[3] Java is also making possible acontroversial new class of cheap machines called network  computers, or NCs, which Sun, IBM, Oracle,Apple, and others hope will proliferate in corporations and our homes.

  The way Java works is simple. Unlike ordinary software applications, which take up megabytes (兆字节) on the hard disk of your PC, Java applications, or “applets”, are little programs that resideon the network in centralized servers. The network delivers them to your machine only when you need them; because the applets are so much smaller than conventional programs, they don’t take forever to download.

   Say you want to check out the sales results from the Southwest region. You’ll use your Internet browser to find the corporate Intranet Website that dishes up financial data and, with a mouseclick or two, ask for the numbers. The server will zap you not only the data,but also the sales-analysis applet you need to display it. The numbers will popup on your screen in a Java spreadsheet, so you can noodle around with them immediately rather than hassle with importing them to your own spreadsheet program.

   To graph the numbers, you’ll call in a charting applet that will let you print outyour report nice and pretty, all without leaving your browser. And you’ll always get the latest, greatest version of the applets too: Since the software is stored in only one place, corporate technicians can keep it up to data moreeasily.

    The real beauty of the Java language,however, is its power to save users money, because it vastly simplifies creating and deploying applications and because it lets them keep theirexisting “legacy” computers and software. Java programs, once written, can run without modification on just about any kind of computer: a PC, a Macintosh, aUNIX workstation—heck, even a mainframe. The underlying operating system makes no difference. Java actually can breathe new life intoolder specialized computers that were at risk of becoming obsolete(淘汰，废弃).

    In scarcely a year, Java has evolvedinto a major challenger to Microsoft’s Windows family of PC operating systems—faster even than DOS and Windows rose to challenge traditional mainframes and minicomputers.[4] Java is also well on its way to becoming the most important Internet software standard, catapulting Sun past Netscape and Microsoft as the leader in Internet computing.

[1] Java is one of the hyped-up Internet software technologies that have spawnedthe World Wide Web, awful words like “intranet”, and those strange-lookingaddresses on business cards and TV commercials.

Java是灸手可热的Internet软件技术中的一种，而这些技术孕育了万维网、“企业网”一类令人生畏的词以及名片上和电视广告中那些怪模怪样的地址。

[2] Originally known as a way to jazz up Web pages with graphic animations—stocktickers that crawl across your screen, for example, and dancing icons—Java hasquickly evolved into a whole lot more.

最初，它是以一种利用图形动画来活跃Web页面的方法而闻名，例如，股票报价从屏幕上慢慢移动以及跳跃的图标，Java很快全面地发展起来。

[3] We’re not just talking word processors and spreadsheets here, but alsoapplications to handle sales, customer service, accounting, databases, andhuman resources—the meat and potatoes of corporate computing.

这里，我们不仅要讨论字处理和电子数据表，还要讨论处理销售、客户服务、记账、数据库和人力资源管理的应用程序——它们是公司(业务、事物、数据等)处理的最基础的部分。

[4] In scarcely a year, Java has evolved into a major challenger to Microsoft’sWindows family of PC operating systems—faster even than DOS and Windows rose tochallenge traditional mainframes and minicomputers.

在不到一年的时间内，Java已成了微软的PC操作系统Windows系列的主要挑战者，它比DOS和Windows挑战传统的大型机和小型机的速度还要快。