• 首先去官網(wǎng)下載jdk8
  http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

• 創(chuàng)建一個(gè)目錄/usr/lib/jvm
  sudo mkdir /usr/lib/jvm

• 解壓縮安裝包至該目錄下
  sudo tar zxvf jdk-8u121-linux-x64.tar.gz -C /usr/lib/jvm

• 進(jìn)入到/usr/lib/jvm目錄下
  cd /usr/lib/jvm

• 把解壓后的jdk1.8.0_25重命名為jdk-8
  sudo mv jdk1.8.0_121 jdk8

• 添加環(huán)境變量
  vim ~/.bashrc

export JAVA_HOME=/usr/lib/jvm/jdk8
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH

• 測(cè)試是否安裝成功
  java -version