下载JDK包
JDK下载链接:https://www.oracle.com/java/technologies/javase-downloads.html
卸载原装java环境
方法一:
rpm -qa | grep java
rpm -e java-1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64 --nodeps
rpm -e java-1.7.0-openjdk-headless-1.7.0.171-2.6.13.2.el7.x86_64 --nodeps
方法二:
which java
rm -rf `which java`
解压安装
tar xf jdk-8u191-linux-x64.tar.gz
mv jdk1.8.0_191/ /usr/local/java
配置环境变量
#export JAVA_HOME=/usr/local/java
#export CLASSPATH=\$JAVA_HOME/lib/tools.jar:\$JAVA_HOME/lib/dt.jar
#export PATH=\$PATH:\$JAVA_HOME/bin
cat << eof >> /etc/profile
export JAVA_HOME=/usr/local/java
export JRE_HOME=\${JAVA_HOME}/jre
export CLASSPATH=.:\${JAVA_HOME}/lib:\${JRE_HOME}/lib:\$CLASSPATH
export JAVA_PATH=\${JAVA_HOME}/bin:\${JRE_HOME}/bin
export PATH=\$PATH:\${JAVA_PATH}
eof
source /etc/profile
查看java版本
java -version
脚本安装
#!/bin/bash
rpm=`rpm -qa | grep java | grep ^java`
rpm -e $rpm --nodeps
tar -zxf jdk-8u191-linux-x64.tar.gz
mv jdk1.8.0_191/ /usr/local/java
cat << eof >> /etc/profile
export JAVA_HOME=/usr/local/java
export JRE_HOME=\${JAVA_HOME}/jre
export CLASSPATH=.:\${JAVA_HOME}/lib:\${JRE_HOME}/lib:\$CLASSPATH
export JAVA_PATH=\${JAVA_HOME}/bin:\${JRE_HOME}/bin
export PATH=\$PATH:\${JAVA_PATH}
eof
source /etc/profile