Setting Java Home in Linux

Edit the .bashrc or .bash_profile file and add the below line:

[$] vi .bashrc

export JAVA_HOME="Enter_the_Java_Home_Directory"

e.g: export JAVA_HOME=/app/JDK/jdk1.8

Here is the complete steps:

https://access.redhat.com/documentation/en-US/JBoss_Communications_Platform/5.0/html/Platform_Installation_Guide/sect-Configuring_Java.html

After updating it, just source the file so it would be effective immediately and you could verify with the below command

[$] source .bashrc

[$] echo $JAVA_HOME

Cheers!
Bose