安装方法
CentOS8上使用 yum 直接安装，环境变量自动配置好
查看是否已安装
看到下面结果，说明已经安装配置 jdk
[root@xxx ~]# java -version
openjdk version "1.8.0_222"
OpenJDK Runtime Environment (build 1.8.0_222-b10)
OpenJDK 64-Bit Server VM (build 25.222-b10, mixed mode)
卸载
查看系统是否自带 jdk
rpm -qa |grep java
rpm -qa |grep jdk
rpm -qa |grep gcj
如果有输出信息，批量卸载系统自带
rpm -qa | grep java | xargs rpm -e --nodeps
如果使用 yum 安装的 jdk，请使用下面命令卸载
yum -y remove java-1.8.0-openjdk-headless.x86_64
查看jdk1.8最新版本
yum install java-1.8.0-openjdk* -y
可以看到如下输出
[root@xxx ~]# yum list java-1.8*
Last metadata expiration check: 0:02:27 ago on Wed 26 Feb 2020 12:55:51 PM CST.
Available Packages
java-1.8.0-openjdk.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-accessibility.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-demo.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-devel.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-headless.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-javadoc-zip.noarch 1:1.8.0.242.b08-0.el8_1 AppStream
java-1.8.0-openjdk-src.x86_64 1:1.8.0.242.b08-0.el8_1 AppStream
安装jdk1.8
yum install java-1.8.0-openjdk* -y
查看当前jdk版本
java -version