install java

https://www.digitalocean.com/community/tutorials/how-to-install-java-on-centos-and-fedora

cd /opt
sudo wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" \
"http://download.oracle.com/otn-pub/java/jdk/8u25-b17/jdk-8u25-linux-x64.tar.gz"

sudo alternatives --install /usr/bin/java java /opt/jdk1.8.0_25/bin/java 1
sudo alternatives --install /usr/bin/javac javac /opt/jdk1.8.0_25/bin/javac 1
sudo alternatives --install /usr/bin/jar jar /opt/jdk1.8.0_25/bin/jar 1