--> yum search java | grep openjdk

--> yum install java-1.8.0-openjdk-headless.x86_64

--> yum install java-1.8.0-openjdk-devel.x86_64

--> update-alternatives --config java #pick java 1.8 and press 1

--> update-alternatives --config javac #pick java 1.8 and press 2