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ISSUES Last revised December 21, 1999.
by Billie PetersonI used to think that Java was something that made life worth living every morning. . . a stop at Starbucks before hitting the trenches. But recently I've been hearing about Java and HotJava as the hottest new items to hit the Internet since the first release of Mosaic. What is this stuff??
--Clueless Coffee Consumer
Dear CCC--
Java is a new programming language that was developed by Sun Microsystems and made available on the Internet in May of 1995. Following is a description of Java from Sun Microsystems: It's a "simple, object-oriented, distributed, interpreted, robust, secure, architecture-neutral, portable, high-performance, multithreaded, and dynamic language." And you say. . .HUH??!!
More simply stated, Java (not an acronym!!) is a programming language based on C++. Java-compatible software can function on any type of machine with a Java-compatible browser, at any time without having to be written for that particular machine/platform. How can this be possible. It's possible because the Java-compatible browser becomes a "virtual machine" inside the client's computer, complete with memory, storage space, and the ability to interpret and compile the instructions needed to operate the Java-compatible software.
What does this mean to the run-of-the-mill Web user? Say you are using a browser, like Netscape, and you discover a video clip that you would like to view. With Netscape 1.1, you click on the link, and it downloads the video clip. Then Netscape looks for a helper application so it can then display the video clip. If Netscape can't find the needed "helper", it whines and gives you the opportunity to hunt for it yourself. If you happen to have the needed application on your machine already, you can still view the video. Otherwise, you either try to find/purchase the needed application or, more likely, you give up and trash the video clip.
In the previous scenario with a Java-compatible browser (HotJava, for example), the browser would download and play the video clip, automatically, seamlessly, as if the application were already on the machine (assuming that the software application needed to play the video clip was also Java compatible).
How does it work? When the browser fetches the requested video clip,it also retrieves a small Java software application (called an applet) needed to view the video clip. The browser then uses its virtual computer to interpret and run the program, going through several levels of security checks to assure that this applet isn't going to do something bad to your computer, like bring in a virus or mess with your files. When you're done with the video clip, the applet may stay on the machine to be used again for other similar files, or it may go away. Applets tend to be very small especially in comparison to modern, full-blown software programs.
What does this mean for Web pages on the Internet? Current web pages are static. If you want to see the CNN Web site updated, you have to click on the "Reload" button and download a new page or set up the browser to reload pages at specified intervals. By using a Java-compatible browser, the CNN page is updated on your computer as soon as it is updated in= Atlanta. If you are viewing a page connected to a live stock market feed as the stock prices change, the display on your screen will change. In thearea of Web page design, Web pages are no longer bound to static color images. Continuous-playing video clips, animation, or other multimedia applications become options. Java not only has the potential for eliminating incompatibility problems, but seamlessly and transparently allows the World Wide Web to become a live, interactive environment.
In addition, there is some discussion about the possibility of eliminating high powered workstations. Instead there would be "thin" systems (or "Internet terminals") which would provide just enough space, memory, power, modem, and monitor to run a good Java-compatible browser. Software on demand becomes the norm. Need to do some specialized spreadsheet work? Click on the spreadsheet link and an appropriate applet is delivered for use and then, perhaps, goes away when it's no longer needed. Someone sends you a formatted document created with a Java-compatible product? Click on the document and the applet allows you to read, edit, and print that document. . . no messy conversion needed. In effect, your browser (because it implements Java) becomes the operating system, the World Wide Web becomes the computer platform, and Java (or whatever evolves from Java) becomes the standard for delivering "stuff", no matter what "stuff" is, where it's going, or where it came from.
What are some problems associated with this new approach? Because it is an interpreted language (each instruction is read and interpreted before the program actually runs), applets will start up more slowly. Also, some people are very concerned over the security issues involved with letting an "unknown" program (the applet) operate on someone's computer. They think that, in spite of the four-tiered security system which functions before the program actually runs, the potential exists for a virus, Trojan Horse, or some other problem to be unknowingly introduced to the system.
Sun Microsystems has released the Java language and its browser, HotJava on the Internet (http://www.javasoft.com/) at no charge. They are betting that they will make their money from the companies that license it for development and that it will, in essence, become the standard. Many companies have already licensed Java or have said that they will license it: Borland International, Lotus Development Corp., Intuit Inc., Macromedia Inc., Netscape, Spyglass Inc., and. . . to the surprise of many. . . Microsoft, Inc.
Currently (February 1996), HotJava and Netscape 2.0 for Windows supports Java. Netscape 2.0 for the Macintosh supports JavaScript. Javascript is an elementary computer language through which limited interactive (Java-like) functions can be easily incorporated into standard HTML code by people who have little or no programming experience. Javascript does not use the Java language in any way.
Java and Java development is still very much in its infancy, and it's challenging to get a grasp of its potential without seeing examples of what's currently been developed using Java or Javascripts.
1) If you have access to a Java-compatible or JavaScript-compatible browser, check out these Web sites:
EarthWeb's Gamelan:
The Directory and Registry of Java Resources/
http://www.gamelan.com/
JavaScript Examples
http://home.netscape.com/comprod/products/
navigator/version_2.0/script/script_info/index.html
JavaScript Index
http://www.c2.org/~andreww/javascript/
Past Featured Java-Powered Pages
http://java.sun.com/applets/
pastFeaturedPages.html
Yahoo! Computers and Internet: Languages: Java: Applets http://www.yahoo.com/Computers_and_Internet/Languages/Java/Applets/
2) Also, a new e-journal JavaWorld (http://www.javaworld.com/), premiered on February 15, 1996.
In addition, check out the following references:
Tech Talk Billie Peterson Moody Memorial Library P.O. Box 97143 Waco TX 76798-7143 Phone# Voice: (817) 755-2344 FAX: (817) 752-5332
WELCOME
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ISSUES Last revised December 21, 1999.