什麼是Java
小編爲大家介紹了什麼是Java，希望對你有幫助哦!
Java is one of the hyped-up Internet software technologies that have spawned the World Wide Web, awfulwords like "intranet", and those strange-looking addresses on business cards and TV commercials. Originallyknown as a way to jazz up Web pages with graphic animations -- stock tickers that crawl across your screen,for example, and dancing icons -- Java has quickly evolved into a whole lot more. To Microsoft''s dismay, itis fast becoming what is known as a computing platform -- a sturdy base upon which programmers can buildsoftware applications.
Java is making possible the rapid development of versatile programs for communicating and collaboratingon the Internet. We''re not just talking word processors and spreadsheets here, but also applications tohandle sales, customer service, accounting, databases, and human resources -- the meat and potatoes ofcorporate computing. Java is also making possible a controversial new class of cheap machines called networkcomputers, or NCs, which Sun, IBM, Oracle, Apple, and others hope will proliferate in corporations and ourhomes.
The way Java works is simple. Unlike ordinary software applications, which take up megabytes on the harddisk of your PC, Java applications, or "applets", are little programs that reside on the network incentralized servers. The network delivers them to your machine only when you need them; because the appletsare 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 browserto find the corporate intranet Website that dishes up financial data and, with a mouse click or two, ask forthe numbers. The server will zap you not only the data, but also the sales-analysis applet you need todisplay it. The numbers will pop up on your screen in a Java spreadsheet, so you can noodle around with themimmediately 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 out your report nice andpretty, all without leaving your browser. And you''ll always get the latest, greatest version of the appletstoo: 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 vastlysimplifies creating and deploying applications and because it lets them keep their existing "legacy"computers and software. Java programs, once written, can run without modification on just about any kind ofcomputer: a PC, a Macintosh, a UNIX workstation -- heck, even a mainframe. The underlying operating systemmakes no difference. Java actually can breathe new life into older specialized computers that were at riskof becoming obsolete.
In scarcely a year, Java has evolved into a major challenger to Microsoft''s Windows family of PCoperating systems -- faster even than DOS and Windows rose to challenge traditional mainframes andminicomputers. 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.
Java是灸手可熱的Internet軟件技術中的一種，而這些技術孕育了World Wide Web、"內部網"一類令人生畏的詞兒以及名片上和電視廣告中那些怪模怪樣的地址。最初，它是以一種利用圖形動畫來活躍Web頁面的一種方法聞名，例如，股票報價從屏幕上慢慢移動和跳躍的圖標，Java很快全面介入。令微軟公司驚愕的是，它很快成了一種被稱作計算平臺的東西--一個能讓程序員開發應用軟件的堅實基礎。
Java正在使快速開發Internet上通信與協同工作的通用程序成爲可能。這裏，我們不僅是談論字處理、電子數據表，而且是能夠處理銷售、客戶服務、記帳、數據庫和人事資源管理的應用程序--它們是公司計算的基礎。Java也使爭論中的一類新的稱之爲網絡計算機(即PC)的便宜計算機成爲可能，SUN、IBM、Oracle、Apple和其它公司希望這種計算機將在公司和家庭中普及開來。
Java工作的方法簡單。與那些要佔用PC機硬盤多兆字節的普通應用軟件不一樣，Java應用程序，即小應用程序，是很小的程序，它常駐在網絡中集中式的服務器上。只有當你需要這種應用程序時，網絡才把它們送到你的機器上;由於小應用程序比常規程序小得多，故下載不需很多時間。
比方說，你要檢查一下西南地區的銷售結果。利用Internet瀏覽器找到能提交財務數據的公司內部網Web點，再用鼠標器點擊一下或兩下，便可調這些數字。服務器將不僅快速給你數據，而且給出顯示它所需的銷售分析小應用程序。這些數字在Java數據表中將浮現到你的屏幕上，因而你能即興地使用它們，而不是麻煩地把它們調入你自己的數據表程序中。爲用圖形表示這些數字，你可以調入作圖表的小應用程序，讓你漂漂亮亮地打印出報表來，而所有這些不必離開瀏覽器。你也能得到最新最好的小應用於程序版本：因爲這種軟件只存儲在一個地方，公司的技術人員可較容易地使其保持最新。
然而，Java語言的真正優點是具有讓用戶省錢和省力，因爲它大大簡化了應用程序的開發與部署使用，而且讓它們保留已有的"傳統"計算機和軟件。Java程序一旦寫好了，就能在任何一種計算機(PC機、Macintosh機、Unix工作站甚至是大型機)上無須修改就能運行。基本的操作系統是沒有差別的。Java實際上給予了那些較舊的專用計算機(有變成廢品風險的產品)新的生命。
在不到一年的時間內，Java已成了微軟的PC操作系統Windows系列的主要挑戰者，比DOS和Windows挑戰傳統的大型機和小型機的速度還要快。Java也在成爲最重要的Internet軟件標準的道路上迅跑，使Sun超過Netscape和微軟成爲Internet計算的領袖。
