【日常记录】Ubuntu安装jdk

1、首先检查Ubuntu版本
`

root@owen:~# uname -a
Linux owen 4.4.0-105-generic #128-Ubuntu SMP Thu Dec 14 12:42:11 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux`

注：x86_64 为64位，i686 为32位

2、打开http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

右键+复制链接地址 http://download.oracle.com/otn-pub/java/jdk/8u161-b12/2f38c3b165be4555a1fa6e98c45e0808/jdk-8u161-linux-x64.tar.gz

wget --no-check-certificate --no-cookies --header “Cookie: oraclelicense=accept-securebackup-cookie” download.oracle.com/otn-pub/java/jdk/8u111-b14/jdk-8u111-linux-x64.tar.gz

创建java目录：mkdir /usr/java
移动jdk到java目录：mv jdk-8u161-linux-x64.tar.gz /usr/java/
进入java目录解压压缩包：tar -zxvf jdk-8u161-linux-x64.tar.gz
配置环境变量：vi /etc/profile
将下面一段加入到配置文件最后：

export JAVA_HOME=/usr/java/jdk1.8.0_161
export JRE_HOME=${JAVA_HOME}/jre  
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib  
export PATH=${JAVA_HOME}/bin:$PATH

立即生效配置：source /etc/profile
检查jdk安装是否成功：java -version

\java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)