Install Java11 on RHEL7

1. Check OS version

#cat /etc/redhat-release

2. Enable optional rpm repository (depending upon your os type)

#yum-config-manager — enable rhel-7-server-optional-rpms
or 
#yum-config-manager — enable rhel-7-workstation-optional-rpms

3. Install the OpenJDK 11 package

yum install java-11-openjdk-devel

4.Set Default Java Version

#sudo alternatives — config java
type the associated number and press Enter.

5. Check the java version

#java -version