Ubuntu, install jdk 1.8.x

$sudo add-apt-repository ppa:webupd8team/java
$sudo apt-get update
$sudo apt-get install oracle-java8-installer

You will see some agreement, yes to all

After installation finished,
$java -version

java version "1.8.0_72"

Java(TM) SE Runtime Environment (build 1.8.0_72-b15)

Java HotSpot(TM) 64-Bit Server VM (build 25.72-b15, mixed mode)

Good luck!