setting the java environement variables

[ramory]

Hi all,

Trying to work with java in my recently installed feisty ,I downloaded Jdk via adept, but I didn't succeed to correctly set the environement variables this is what I did :
export JAVA_HOME=/usr/lib/jvm/java-1.6.0-sun-1.6.0.00
and then
$ export PATH=$PATH:$JAVA_HOME/bin
but when I open a new terminal and do
$ echo $JAVA_HOME
i get nothing... I really don't understand what I did wrong!!

[meatpan]

The reason you cannot see JAVA_HOME is because you opened a new terminal. When a new terminal is opened, the session environmental variables are set to their defaults. JAVA_HOME will still be defined in the terminal where it was originally input, but not a new terminal.

You can change the default user environment variables by editing the ~/.bashrc file. The bashrc file is read every time you open a terminal or when you log in to the machine. (note, .bash_profile is also read when you first log in).

A java setup can require a *lot* of environment tweaking, so here are two commands that you might find useful for inspecting your environment:

1. env. This command will simply print out the environmental variables that would be available to a command you execute.
2. set. Straight from the set manual, "Without options, the name and value of each shell variable are displayed.

I

[ramory]

Hi,

these must sound stupid but what exactly do I need to edit in the ~/.bashrc file??
I didn't find where I can specify the JAVA_HOME and add it directory to the PATH!

thank you..

[meatpan]

The commands you typed in the shell should be adequate for the ~/.bashrc file. Here is what you wrote:

export JAVA_HOME=/usr/lib/jvm/java-1.6.0-sun-1.6.0.00
export PATH=$PATH:$JAVA_HOME/bin


Try copying that snippet into the ~/.bashrc. Open a new terminal, try the env command (for example: "env | grep -i java"), and see if it worked.

edited: code tags

[ramory]

THANX a lot !!!
it worked just fine thank you...

[kawk]

hello

I would like to ask how do I let eclipse know about the java_home since it uses the default java installed with ubuntu???

[nitro_n2o]

For configuring eclipse:
Go to: window -> preferences -> Java (on the left side) -> Installed JREs
Then click on Add.. browse for your java_home and select it

Hope that helps

[ekanata]

I use these instruction to tell which java to use:

update-java-alternatives -l
sudo update-java-alternatives -s <your_chioce>
If I already know which java to use, then I don't need the first instruction to show the available versions.
That's what I learn from here (http://www.schabell.com/2006/11/ubuntu-java-moving-from-14-to-15-using.html).

[nicktmro]

Putting the JAVA_HOME in your .bashrc won't help if you need to create a launcher for Eclipse for example.

The .bashrc variable will only be available when you use a terminal.

I think the best place to put your JAVA_HOME is the /etc/environment file as this will be picked up from X as well.

Have a look at http://tmro.blogspot.com/2007/07/ubuntu-and-java-javahome-no-longer.html

HTH