CentOS7 use YUM to install JDK

command

yum install java-1.8.0-openjdk  java-1.8.0-openjdk-devel

　　

 

Environment Variables

vi  /etc/profile　　

At the end of Accession:

export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.242.b08-0.el7_7.x86_64
export CLASSPATH=.:$JAVA_HOME/jre/lib/rt.jar:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$PATH:$JAVA_HOME/bin

　　Note Version Path