Centos7.4下安装与卸载Jdk1.8

卸载

查看已经安装的jdk

[root@hugo]# rpm -qa|grep jdk
java-1.8.0-openjdk-headless-1.8.0.65-3.b17.el7.x86_64
java-1.7.0-openjdk-1.7.0.91-2.6.2.3.el7.x86_64
java-1.7.0-openjdk-headless-1.7.0.91-2.6.2.3.el7.x86_64
java-1.8.0-openjdk-1.8.0.65-3.b17.el7.x86_64

• 
  

卸载命令

[root@@hugo]# yum -y remove java-1.8.0-openjdk-headless-1.8.0.65-3.b17.el7.x86_64

• 
  

卸载完成之后Java命令不被识别

[root@@hugo]# java -version
bash: java: command not found...

• 
  

安装

去官网下载jdk：http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
解压到安装目录

[root @hugo ] # mkdir /usr/local/java

[root @hugo setup] # tar -zxvf jdk-8u161-linux-x64.tar.gz -C /usr/local/java/

• 
  

安装完毕之后在/etc/profile文件末尾添加

[root@ h ugo java]# ln -s jdk1.8.0_161/ default

[root@ hugo] # vim /etc/profile

# vi

alias vi=vim

#jdk
export JAVA_HOME=/usr/local/java/default
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH

使/etc/profile生效

[root@hugo]# source /etc/profile

• 
  

检测安装是否成功

[root@hugo java]# java -version
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)