1.安装jdk

[root@localhost ~]#tar xf 755 jdk-8u171-linux-x64.tar.gz

[root@localhost ~]#mkdir /usr/java

[root@localhost ~]#mv jdk1.8.0_171 /usr/java/

2.配置环境变量

[root@localhost ~]#vi /etc/profile 在最后加入

export JAVA_HOME=/usr/java/jdk1.8.0_171     #jdk安装目录

export PATH=$JAVA_HOME/bin:$PATH

3.使配置生效

[root@localhost ~]#source /etc/profile

4.验证安装

如果显示jdk版本为jdk1.8即为安装成功

[root@localhost ~]java -version

java version "1.8.0_171"

Java(TM) SE Runtime Environment (build 1.8.0_171-b08)

Java HotSpot(TM) 64-Bit Server VM (build 20.45-b01, mixed mode)