РефератыИностранный языкJaJava Essay Research Paper Java is the

Java Essay Research Paper Java is the

Java Essay, Research Paper


Java is the substance whose aroma is awakening the Internet community.


It is a new programming language developed by Sun Microsystems that has


much in common with the beverage that shares its name. It’s good, it’s


hot, and people know it around the world. Java (the programming language)


beats the other stuff hands down though, it’s free. Many have heard of


Java, yet few know what it is, or what it can do. It certainly has the


potential to become a part of our everyday lives, existing in our mobile


phones, televisions, and Internet browsers. If you are interested in your


future read on.


Java is still in its infancy stage, yet to fulfil its intended


purpose. Designed in 1990 as an embedded language for consumer


electronics, it was later discovered to be an ideal interface to the


Internet. In 1996, Netscape added Java support to its popular Navigator


Web browser. The Web began to stir from its static text coma as excited


programmers began to incorporate Java applications, “applets”, into their


Web pages.


An applet is like an application, but it doesn’t run stand-alone.


An applet must adhere to a set of conventions that allows it to run within


a Java-compatible browser. The technology is still evolving, and today,


most Java applets are simple animations, or user interactions. The future


is brighter, promising full-blown applications over the Internet; imagine


using Microsoft Office from your television. For now, though, those who


have experienced an applet may be left disappointed. A casual user is


unlikely to be impressed with scrolling text, or simple animations,


especially if they must pay for them with increased download times.


Behind the scenes, unbeknownst to them, truly amazing things are


happening.


A Java applet begins its life by being “called” by a Web page. To be


technologically correct, the applet is embedded in the Web page. The Web


browser then downloads the applet and runs it on your machine. If you


just missed the amazing part: it runs on your machine. How can a program


from an unknown source be trusted to run on your computer without your


permission? It can’t unless that program was created using a secure


language like Java, and then wrapped with a secure viewing browser like


Netscape Navigator. The concept of being able to run applications on your


system is significant for several reasons. If you want to see a picture,


but don’t have a picture viewer, you can get both at once. This


eliminates the problem of not having the correct helper application or


even worse: having to settle for what’s available. The ability to run


applications on your system has another significant advantage.


Traditionally when you view something that “runs” on a Web page, or is


interactive, the work takes place on the remote computer, not yours.


Java frees Internet resources, allowing the work to take place on the


client’s system rather than the server’s.


If all applications were run on remote computers, the servers would be


inundated with traffic, and these collectively would propagate to bring


the entire Internet to a grinding halt. With a growing Internet


population, the prospect of this

is real. There is a better way. If it


can be done safely, isn’t it quicker, not to mention more considerate, to


get what you need, take it with you, and use it on your time? A good


analogy is a long bank queue, with everyone waiting for the person in


front of them to finish. Some will be quick, and others will attempt a


hostile takeover on your lunch hour. Imagine a different world where


tellers were issued at the bank. Instead of waiting for a teller to


become free, you could simply take the teller you require from an almost


endless supply, then complete your transaction without delaying the people


behind you. You would only have to wait in line to get a teller. If the


bank got hundreds of new customers every day, would there be any other way


to do it? The issue of security would still have to be addressed. Away


from the work environment, how could you trust the teller you got? The


bank manager wouldn’t be around to oversee her. You would have to put her


in a sandbox.


A sandbox is the name given to the concept of setting the


boundaries in which a Java applet can “play”. A Java applet cannot look


at arbitrary files on the machine it’s running on, or have unauthorized


access to system resources. It can’t introduce a virus or other malicious


logic, delete critical files, or gain access to your passwords unless you


allow it to. It is security measures like the sandbox that make Java much


more than just a new programming language. Meet Java, the run-time


environment.


If Java were just another programming language, the industry would have


greeted its introduction with a resounding yawn. What makes Java


intriguing is that it is also a runtime environment embodied in what is


called a virtual machine (VM). This VM sits, in essence, between the Java


program and the machine it is running on, offering the program an abstract


computer that executes the Java code and guarantees certain behaviors


regardless of the underlying hardware or software platform. Java compilers


thus turn Java programs not into language for a particular machine but


into a platform-neutral byte code that the machine-specific VM interprets


on the fly1. A Java compiler is like a translator who translates a


language to a common ground like English. Since English is known around


the world, specific translators, like the VM, are able to translate


English into the language specific for their country. With so many


different computers connected to the Internet, platform independence is


necessary.


Java has been thrust into the spotlight with its new language built on the


core values of security and platform independence. Sun Microsystems has


promised a “Write once, run anywhere” language suited to an Internet


community comprised of a smorgasbord of different computer, hardware, and


software configurations. The power to write programs that run on most


everyone’s computer is revolutionary. For Internet applications, though,


the value of platform independence degrades exponentially without strict,


built-in security. Java provides this security, and has the power to


change the way we compute.


1 PC Magazine: Your Guide to Java for 1998 — Your Guide to Java for 1998 4/7/98

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