卸载
查看已经安装的jdk
[root@bogon jre]# 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
rpm -e --nodeps java-1.8.0-openjdk-1.8.0.102-4.b14.el7.x86_64
-e 表示卸载
--nodeps 表示不考虑是否有依赖问题,强制卸载
安装
去官网下载jdk:Java Downloads | Oracle
解压到安装目录
[root@bogon software]# tar -zxvf jdk-8u101-linux-x64.tar.gz -C /usr/local/java/
安装完毕之后在/etc/profile文件末尾添加
[root@bogon software]# vim /etc/profile
jdk1.8:
export JAVA_HOME=/usr/local/java/jdk1.8.0_101
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH
jdk11:
export JAVA_HOME=/usr/local/jdk-11.0.5
export PATH=$JAVA_HOME/bin:$PATH
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
使/etc/profile生效
[root@bogon jdk1.8.0_101]# source /etc/profile
检测安装是否成功
[root@bogon jdk1.8.0_101]# java -version
java version "1.8.0_101"