This script will export many useful environment variables related to Java SDK.

set_jdk_env.sh

#!/bin/bash
# ##########################################################
# set_jdk_env.sh
# This script will export many useful environment variables
# related to Java SDK.
# Wesley Rodrigues da Silva <wesley.it at gmail.com>
# LICENCE CREATIVE COMMONS BY - 2014
# http://creativecommons.org/licenses/by/2.0/legalcode
# ##########################################################

## Where is your JDK folder?
export JDK_HOME="/opt/jdk8"

## Ok, don't change this
export SDK_HOME="$JDK_HOME"
export JAVA_HOME="$JDK_HOME"
export JAVA_ROOT="$JDK_HOME"
export JRE_HOME="$JDK_HOME/jre"
export JAVA_BINDIR="$JDK_HOME/bin"
export PATH="$JAVA_BINDIR:$PATH"