Pre-Install

sudo apt-get install software-properties-common

https://packages.ubuntu.com/zh-tw/trusty/software-properties-common

Install Oracle Java8

sudo add-apt-repository "deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main"
sudo apt-get update
sudo apt-get install oracle-java8-installer
javac -version

Install Oracle Java9

sudo apt-get install oracle-java9-installer

Java version manager

sudo update-alternatives --config java

SET JAVA_HOME

Modified ~/.profile

vim ~/.profile

Append JAVA_HOME to environment

# JAVA_HOME
JAVA_HOME="/usr/lib/jvm/java-8-oracle"

# JAVA version manange controller aliases
alias jvc='sudo update-alternatives --config java'

Verify

source ~/.profile
echo $JAVA_HOME
jvc

jerry@local:~$ jvc
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                     Priority   Status
------------------------------------------------------------
  0            /usr/lib/jvm/java-9-oracle/bin/java       1091      auto mode
* 1            /usr/lib/jvm/java-8-oracle/jre/bin/java   1081      manual mode
  2            /usr/lib/jvm/java-9-oracle/bin/java       1091      manual mode

Press enter to keep the current choice[*], or type selection number: 1

Reference

https://www.digitalocean.com/community/tutorials/how-to-install-java-with-apt-get-on-debian-8