1. install
jre
$sudo yum install java -y
jdk
$sudo yum install java-1.8.0-openjdk-devel
2. set path
$sudo vi /etc/profile
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.345.b01-1.el7_9.x86_64
export CLASSPATH=.:$JAVA_HOME/jre/lib/:.
export PATH=$PATH:$JAVA_HOME/bin
$su - root
#source /etc/profile
About path
3.3. INSTALL OPENJDK ON RED HAT ENTERPRISE LINUX - 2.Optional: Set the JAVA_HOME environment variable