CODEWITHSUNDEEP
linux
teddy
teddy

Reputation: 423

How to set java environment variables using shell script

I know I can just type $ vi .bashrc

export JAVA_HOME=/usr/lib/jvm/java-7-oracle
export PATH=$JAVA_HOME/bin:$PATH

However how to use shell script to do it? I prefer to write shell script because I need to configure multiple servers, if type one by one I would take me a long time to go.

Can someone guide me how to do this? Thanks a lot!

Upvotes: 3

Views: 20647

Answers (1)

Adam Gausmann
Adam Gausmann

Reputation: 322

EDIT: I just realized that you wanted a script to automate the process of adding environment variables. These commands may work for you:

echo "export JAVA_HOME=/usr/lib/jvm/java-7-oracle" >>~/.bashrc
echo "export PATH=$JAVA_HOME/bin:$PATH" >>~/.bashrc

What this does is append the given text to .bashrc. Instead of copying .bashrc files from server to server, run these commands (you could probably write a script for these) on each server. This preserves the contents of the original rc files on each server, which I find is a better idea than completely overwriting the file.

Original answer

Your .bashrc file is actually written as a shell script. You would place the exact same lines in the shell script, possibly with a hashbang at the beginning of the file. For example:

#!/bin/bash

export JAVA_HOME=/usr/lib/jvm/java-7-oracle
export PATH=$JAVA_HOME/bin:$PATH

# do java stuff here...

If you were to "do java stuff" in this script, this would work fine. However, if these variables are going to be used outside of the script, you would have to "source" this file. That is what happens with .bashrc. Before the first prompt is given, Bash runs source ~/.bashrc to publish the variables defined in .bashrc.

Upvotes: 5

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