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SHAPE ="RECT" HREF ="/reference/author.html" COORDS ="361,0,440,29"><AREA SHAPE ="RECT" HREF ="/reference/basic.html" COORDS ="254,0,360,29"><AREA SHAPE ="RECT" HREF ="/reference/help.html" COORDS ="183,0,251,29"><AREA SHAPE ="RECT" HREF ="/reference/cool.html" COORDS ="100,0,181,29"><AREA SHAPE ="RECT" HREF ="/reference/mybook.html" COORDS ="0,0,100,29"></MAP><MAP NAME ="header_r1.gif.map"><AREA SHAPE ="RECT" HREF ="/reference/personalize.html" COORDS ="339,0,439,29"></MAP><p><font face="Arial,Helvetica" size="-1" color="#006666"><A HREF="/reference/r_library.html"><B>All Categories</A> :</B><b><A HREF="/reference/r_java.html">Java</A></b></font><p><META><H1><FONT SIZE=6 COLOR=#Ff0000>Chapter 1</FONT></H1><H1><FONT SIZE=6 COLOR=#Ff0000>Java Overview</FONT></H1><HR><P><CENTER><B><FONT SIZE=5><A NAME="CONTENTS">CONTENTS</A></FONT></B></CENTER><UL><LI><A HREF="#TheJavaStory">The Java Story</A><LI><A HREF="#IntroducingJava">Introducing Java</A><LI><A HREF="#JavaPrograms">Java Programs</A><LI><A HREF="#TheJavaDevelopersKit">The Java Developer's Kit</A><LI><A HREF="#WhereIsJava">Where Is Java?</A><LI><A HREF="#ExampleInstallingHotJava">Example: Installing HotJava</A><LI><A HREF="#ExampleInstallingtheJDK">Example: Installing the JDK</A><LI><A HREF="#Summary">Summary</A><LI><A HREF="#ReviewQuestions">Review Questions</A><LI><A HREF="#ReviewExercises">Review Exercises</A></UL><HR><P>Anyone who's had anything to do with computers in the '90s knowsthat the Internet is all the rage. The immense growth of thisglobal computer network has not only created a handy way to downloadfiles and information but has also sparked major controversiesover freedom of speech, copyright law, and computer security.Hardly a day goes by without the Internet making the news.<P>But not all Internet activity is steeped in controversy. One ofthe more positive Internet newsmakers has been the release ofJava, a computer programming language that enables folks likeyou and me to easily create applications that can be used acrossthe Internet without worrying about platform compatibility ornetwork security. The two types of Java applications-applets foruse within World Wide Web pages and stand-alone Java applications-areguaranteed to do more to liven up the World Wide Web than eventhe most heated controversy.<P>Java, however, was conceived long before its suitability for theInternet was noted and taken advantage of. You may be surprisedto learn that Java was developed for a very different use. Infact, "Java" isn't even the language's original name.In this chapter, you'll get a quick look at Java's history, aswell as learn why Java is an excellent tool for creating Internetapplications.<H2><A NAME="TheJavaStory"><FONT SIZE=5 COLOR=#Ff0000>The Java Story</FONT></A></H2><P>Back in 1990, a gentleman by the name of James Gosling was giventhe task of creating programs to control consumer electronics.Gosling and his team of people at Sun Microsystems started designingtheir software using C++, the language that most programmers werepraising as the next big thing because of its object-orientednature. Gosling, however, quickly found that C++ was not suitablefor the projects he and his team had in mind. They ran into troublewith complicated aspects of C++ such as multiple inheritance ofclasses and with program bugs such as memory leaks. Gosling soondecided that he was going to have to come up with his own, simplifiedcomputer language that would avoid all the problems he had withC++.<P>Although Gosling didn't care for the complexity of languages suchas C++, he did like the basic syntax and object-oriented featuresof the language. So when he sat down to design his new language,he used C++ as its model, stripping away all the features of C++that made that language difficult to use with his consumer-electronicsprojects. When Gosling completed his language-design project,he had a new programming language that he named Oak. (The storygoes that the name Oak came to Gosling as he gazed out his officewindow at an oak tree.)<P>Oak was first used in something called the Green project, whereinthe development team attempted to design a control system foruse in the home. This control system would enable the user tomanipulate a list of devices, including TVs, VCRs, lights, andtelephones, all from a hand-held computer called *7 (Star Seven).The *7 system featured a touch-sensitive screen that the ownerused to select and control the devices supported by the control.<P><CENTER><TABLE BORDER=1 WIDTH=80%><TR VALIGN=TOP><TD><B>NOTE</B></TD></TR><TR VALIGN=TOP><TD><BLOCKQUOTE>The *7 screen display featured a number of animated figures, of which Duke (now the little guy considered to be the Java mascot) was one. Once you get involved with Java, you're liable to see a lot of Duke, who pops up on the Sun Microsystems Web site (Figure 1.1), and who is featured in some of Sun's sample Java applets.</BLOCKQUOTE></TD></TR></TABLE></CENTER><P><P><A HREF="f1-1.gif"><B> Figure 1.1 : </B><I>Duke has become the Java mascot.</I></A><P><P>The next step for Oak was the video-on-demand (VOD) project, inwhich the language was used as the basis for software that controlledan interactive television system. Although neither *7 nor theVOD project led to actual products, they gave Oak a chance todevelop and mature. By the time Sun discovered that the name "Oak"⌨️ 快捷键说明
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