Installation & Configuration JDK8 on Ubuntu/Linux Mint

sudo add-apt-repository ppa:webupd8team/java  

sudo apt-get update  

sudo apt-get install oracle-java8-installer

java -version

sudo vi /etc/environment

Added in the file

JAVA_HOME="/usr/lib/jvm/java-8-oracle"

Save the exit

:wq

source /etc/environment

echo $JAVA_HOME