jdk-8u181-linux-x64.tar.gz
tar -zxvf jdk-8u181-linux-x64.tar.gz
vim /etc/profile
JAVA_HOME=/opt/soft/jdk1.8.0_181 PATH=$PATH:$JAVA_HOME/bin export JAVA_HOME PATH
source /etc/profile
export JAVA_HOME=/java/jdk-12.0.1 export JRE_HOME=$JAVA_HOME/jre export CLASSPATH=.:$JAVA_HOME/lib:$JRE_HOME/lib:$CLASSPATH export PATH=.:$JAVA_HOME/bin:$JRE_HOME/bin:$KE_HOME/bin:${MAVEN_HOME}/bin:$PATH