查看Java JDK 安装位置
三步法:
# java程序的执行路径
which java
/usr/bin/java
ls -l /usr/bin/java
lrwxrwxrwx 1 root root 22 Feb 14 22:16 /usr/bin/java -> /etc/alternatives/java
ls -l /etc/alternatives/java
lrwxrwxrwx 1 root root 35 Feb 14 22:16 /etc/alternatives/java -> /usr/java/jdk1.8.0_121/jre/bin/java
其它
# 如果配制了环境变量,则可以
echo $JAVA_HOME
# rpm -ql java