History of Tunnel and Java
From Fs_wiki
Tunnel is written in a language called Java, first released by Sun Microsystems in 1995. It quickly gained reputation for being slow and buggy which it no longer deserves. Java is readily available for Windows from Sun, however under Linux there are several versions with varying levels of freeness and completion. Tunnel should be able to work for Java 1.4.
Often people accidentally get the "JRE" (Java Runtime Environment) instead of the "JDK" (Java Development Kit). This is much smaller and is able to run Tunnel, but not compile it. There's also a J2EE (Enterprise Edition), and a J2SE (Standard Edition), but I don't know what's in them.
Java is a massive system with many optional modules. Tunnel only uses the core system. Java's version numbering is extremely confusing. While the language itself has progressed through a series of reasonable version numbers (from 1.0 to 1.1, 1.2, 1.3, 1.3.1, 1.4, and most recently 1.5), the file you download from the website can be called almost anything, and your guess is as good as mine as to what the numbers mean. I believe that version 1.1 of Java was called "Java2" in some quarters, and the number after the "1." is sometimes refered to as the Java2 version number.
Once you have downloaded your copy of Java and installed it (probably by running an ".exe" file), you should be able to run it from the command line...
For those who don't know what a command line is, and are using Microsoft Windows, you get it by clicking on Start, and Run..., typing cmd into the box, and hitting return. That is the command line. It's a black window with a cursor.
If everything is going well, you should be able to type:
> java -version
and get it to print-out the version number of the Java Runtime Environment you have just installed as part of the JDK. If you can't get this to happen, it hasn't been installed properly, or the path variables have failed to get set, or something else is wrong. There is little point in proceding further.
If you are lucky you will also be able to run the Java Compiler from the command line.
> javac
Usually this doesn't work because the compiler doesn't get included on the path list, and you have to command it explicitly with a line like:
> "C:\Program Files\Java\j2sdk1.5.0\bin\javac.exe"
(don't forget to type the quotes, because of the space in the name) and then you should see it run. Other variations are "jdk1.5.0" and "j2sdk1.5.0_05"; they keep changing it with the versions, which is why I can't make it easy for you. You have to find it in your file system using the "Windows Explorer".
If this works, it will print a whole lot of interesting stuff instead of
'javac' not recognized as an internal or external command
It's a good idea to make this work, but not the end of everything if you can't since you can download Tunnel in an already compiled form. However, doing so makes it harder to get the latest features and bug fixes.
