How to set Environmental Variable?

Question

Please tell me how to set environment variables

JAVA_HOME
MAVEN_HOME
TOMCAT_HOME
PATH

I installed Java via terminal apt-get command, Tomcat and Eclipse by downloading tar.gz files and extracting them. Maven also by terminal and by getting plugin to eclipse too.

Please tell me a answer step by step. I'm beginner to Ubuntu.

Answer 1

Go to a terminal and type :

export JAVA_HOME=/usr/lib/jvm/java-6-sun

and consequently for the others

Don't forget these values will be only available in your current terminal session. You'll have to add these to a persistent environnement file like ~/.bashrc or ~/.zshrc to keep them among a terminal session restart

To check for existing variables, type env

Answer 2

It's not really clear whether you want to set from a program or what, but, in a bash shell, the syntax is: export JAVA_HOME=/path/to/JDK