centos安装jdk

下载并解压jdk

wget --no-check-certificate --no-cookies --header "Cookie: oraclelicense=accept-securebackup-cookie" https://download.oracle.com/otn-pub/java/jdk/8u191-b12/2787e4a523244c269598db4e85c51e0c/jdk-8u191-linux-x64.tar.gz #下载jdk1.8
tar -zxvf jdk-8u191-linux-x64.tar.gz #进行解压
mv jdk1.8.0_191/ /usr/local/jdk

修改环境变量

vim /etc/profile #修改环境变量

#java environment
export JAVA_HOME=/usr/local/jdk #这个目录要写你解压jdk的那个目录
export CLASSPATH=.:${JAVA_HOME}/jre/lib/rt.jar:${JAVA_HOME}/lib/dt.jar:${JAVA_HOME}/lib/tools.jar
export PATH=$PATH:${JAVA_HOME}/bin

source /etc/profile #使配置文件重新加载

检查是否成功

java -version #出现对应版本即正确