How To - Java

last update 12^th Feburary 2002
The latest Version can be found at http://home.vr-web.de/jSwi/SoftDesk/HowToJava.html

Juergen Schwister / Cologne / Germany
MailTo:Juergen.Schwister@gmx.net
http://home.vr-web.de/jSwi

Why Java

Java is a Programming language which can be used on many Platforms like Windows™, MAC OS™, Linux, Unix, OS/390™, AS400™ and some more. For each plattform is Java Runtime Environment available. On the one hand you need a compiler (JAVAC) to generate Class files (*.class) from source Files (*.java), on the other hand you need a Java Runtime Environment (JRE) to execute the class files. The class files do not need to be compiled on each platform. Once compiled they will run on nearly every JRE.

Where to get a JRE (Java Runtime Environment)

Look at Sun ,IBM or Apple to get the JRE.

What is a JDK (Java Development Environment)

The JDK contains all the neccesary files to create you own Java Applications;including a Compiler, a JRE, a debugger and other Tools for development and deployment.

What is a JAR file (Java Archive)

A JAR File is a file containis the neccesary class files to run a Java Application. The class files can decompressed with WinZip™ or Stuffit™ but there is no need to do so, because the JRE can handle such JAR files.