centos7 安装jdk

1. 下载jdk
   http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

2. 创建目录
   mkdir /usr/local/java/

3. 解压到目录
   tar -zxvf jdk-8u171-linux-x64.tar.gz -C /usr/local/java/

4.配置环境变量
vim /etc/profile

vim /etc/profile

export JAVA_HOME=/usr/local/java/jdk1.8.0_241
export JRE_HOME={JAVA_HOME}/lib:{JAVA_HOME}/bin:$PATH

source /etc/profile

ln -s /usr/local/java/jdk1.8.0_241/bin/java /usr/bin/java

5.验证
java -version