THDL Toolbox > THL Technologies & Open Standards > Technologies For Dummies > Java
What is Java?
Simple Introduction to Java
For installation instructions, click here.
Description
Several of our tools are based on Sun's open and standards-based "Java" technology, a powerful cross-platform programming environment. Since code written in Java runs the same regardless of the underlying operating system, Java programmers can "write once" and "run everywhere".
Here's how Java works: first, a programmer writes some Java source code. Next, the source code is compiled into Java byte code by the Java Compiler. This byte code is then interpreted by a Java Virtual Machine (JVM), an application which acts as an intermediary between the byte code and the native operating system.
Currently, JVMs exist for all major operating systems, including Windows 95+, Linux, Solaris, and Mac OS X. Since Jskad, Savant, QuillDriver and the Translator Tool all require relatively recent versions of Java, they will not run on older Mac operating systems.
Because Java applications are run by a JVM, they tend to be slower than applications written in the C language. However, with the ever-increasing speed of modern PCs, we feel confident that most users will be unaffected by Java's slower performance.
Most of our Java tools run via Java Web Start (JWS), a new technology which Sun now bundles together with every Java download. JWS allows Java applications to be launched directly from a browser. JWS is a more robust technology than the familiar but historically relatively unsuccessful Java Applets. Among other features, JWS creates desktop shortcuts to your Java applications, letting you run these applications either online or offline. In addition, if necessary, JWS automatically updates your applications when you are online.
When you first run a JWS-based application from a website, the JWS launcher application pops up and downloads the application to your local hard drive. When you run the program for a second time, JWS offers to make a short cut icon on your desktop or elsewhere to quickly open the application without needing to go to the website again. Regardless of whether you make the short cut, the application is locally installed, so that you can subsequently run it whether you are online or not. In addition, anytime you run the application while connected to the Internet, JWS will check the original website to see if any new versions of the application have been released; if there are newer versions, then it will automatically update your version. Thus, you should at least occasionally run your JWS applications while you are online.
For useful information on Java Web Start, please visit its home page, as well as the VAMP Headquarters.
How is Java being used in THDL?
TBA.
How Can I Explore Java Further?
TBA.