思路：jdk8 采用解压缩模式，jdk11采用安装模式，然后在jenkins中指定jdk路径
下载解压缩jdk8
https://www.oracle.com/java/technologies/downloads/#java8
解压缩：jdk-8u391-linux-i586.tar.gz
/lib/ld-linux.so.2: bad ELF interpreter: 没有那个文件或目录
yum install glibc.i686
安装jdk11
安装
yum -y install java-11-openjdk
卸载
yum remove -y java-11-openjdk.x86_64
yum remove -y java-11-openjdk-headless.x86_64
查找已经安装的
yum list installed *java*
yum list installed
找java和jdk
卸载
yum remove java-1.8.0-openjdk-headless.x86_64
其他参考命令
yum install wget
yum clean all
yum makecache
yum -y install gcc
yum -y install gcc-c++
yum install -y jenkins
yum install -y vim
yum install -y git
yum install -y unzip
yum install java-1.8.0-openjdk -y
yum remove java-1.8.0-openjdk -y
rpm -qa | grep java
jenkins中指定
