$ yum install -y java-1.8.0-openjdk-devel.x86_64
配置環境變量
# 修改 ~/.bash_profile 也行
$ vim /etc/profile.d/java.sh
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.181-7.b13.el7.x86_64
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$JAVA_HOME/bin:$PATH