1、查看系统、java安装情况
[root@linuxprobe ~]# cat /etc/system-release
Red Hat Enterprise Linux release 8.0 (Ootpa)
[root@linuxprobe ~]# java
bash: java: command not found...
Failed to search for file: Cannot update read-only repo
[root@linuxprobe ~]# java -version
bash: java: command not found...
Failed to search for file: Cannot update read-only repo
[root@linuxprobe ~]# which java
/usr/bin/which: no java in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)
2、下载安装包、给执行权限
下载地址：https://www.oracle.com/java/technologies/javase-jdk15-downloads.html
[root@linuxprobe software]# ls
jdk-15_linux-x64_bin_2.rpm
[root@linuxprobe software]# chmod 755 jdk-15_linux-x64_bin_2.rpm
[root@linuxprobe software]# ll -h
total 162M
-rwxr-xr-x. 1 root root 162M Oct 17 02:47 jdk-15_linux-x64_bin_2.rpm
3、安装
[root@linuxprobe software]# rpm -ivh jdk-15_linux-x64_bin_2.rpm
warning: jdk-15_linux-x64_bin_2.rpm: Header V3 RSA/SHA256 Signature, key ID ec551f03: NOKEY
Verifying... ################################# [100%]
Preparing... ################################# [100%]
Updating / installing...
1:jdk-15-2000:15-ga ################################# [100%]
4、检测安装效果
[root@linuxprobe software]# java ## 已经可以调用
Usage: java [options] <mainclass> [args...]
(to execute a class)
or java [options] -jar <jarfile> [args...]
(to execute a jar file)
or java [options] -m <module>[/<mainclass>] [args...]
java [options] --module <module>[/<mainclass>] [args...]
(to execute the main class in a module)
[root@linuxprobe software]# java -version
java version "15" 2020-09-15
Java(TM) SE Runtime Environment (build 15+36-1562)
Java HotSpot(TM) 64-Bit Server VM (build 15+36-1562, mixed mode, sharing)
[root@linuxprobe software]# which java
/usr/bin/java
5、卸载
[root@linuxprobe software]# rpm -qa | grep jdk
jdk-15-15-ga.x86_64
[root@linuxprobe software]# rpm -e --nodeps jdk-15-15-ga.x86_64
6、查看卸载效果
[root@linuxprobe software]# java ## 没问题
-bash: /usr/bin/java: No such file or directory
[root@linuxprobe software]# java -version
-bash: /usr/bin/java: No such file or directory
[root@linuxprobe software]# which java
/usr/bin/which: no java in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)
参考：https://blog.csdn.net/u010993514/article/details/82926514
原文：https://www.cnblogs.com/liujiaxin2018/p/13828298.html