操作系统：CentOS Linux release 7.4.1708 (Core)
JDk版本：JDK 1.8
JDK下载地址:https://www.oracle.com/technetwork/java/javase/downloads/index-jsp-138363.html
下载对应版本，这里采用RPM包与二进制包两个方法分别安装
方法一
# yum install jdk-8u202-linux-x64.rpm -y
查看版本
# java -version
java version "1.8.0_202"
Java(TM) SE Runtime Environment (build 1.8.0_202-b08)
Java HotSpot(TM) 64-Bit Server VM (build 25.202-b08, mixed mode)
检查是哪个RPM包提供了java文件
# rpm -q --whatprovides java
jdk1.8-1.8.0_202-fcs.x86_64
方法二
二进制包安装
# tar -xzvf jdk-8u40-linux-x64.tar.gz
# mv jdk1.8.0_40 /usr/local/jdk
配置环境变量
# vim /etc/profile
export JAVA_HOME=/usr/local/jdk
export PATH=$JAVA_HOME/bin:$PATH
# source /etc/profile
查看版本
# java –version
java version "1.8.0_40"
Java(TM) SE Runtime Environment (build 1.8.0_40-b26)
Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode)
参考资料：https://docs.oracle.com/javase/8/docs/technotes/guides/install/install_overview.html
