Here are many programs and scripts that require java to run it, but usually Java is not installed by default on VPS or Dedicated Server. This article assumes you have at least basic knowledge of linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple. I will show you through the step by step installation Java JDK 9 on Ubuntu 15.04.
Note: Java 9 is not a stable release, so I recommend you to use java stable release 8 for productions servers.
Install Java JDK 9 on Ubuntu 15.04
Step 1. Remove the OpenJDK from the system, if you have it already installed.
sudo apt-get remove --purge openjdk*
Step 2. Add the webupd8team Java PPA repository in your system.
ssudo add-apt-repository ppa:webupd8team/java
Step 3. Install Java JDK 9.
After added the PPA, run commands below one by one to install Java:
sudo apt-get update
sudo apt-get install oracle-java9-installer
Once the script successfully installs Java 9 on your system, you may run command to set ava 9 environment variables:
sudo apt-get install oracle-java9-set-default
Step 4. Verify Installed Java Version.
java version "1.9.0-ea"
Java(TM) SE Runtime Environment (build 1.9.0-ea-b50)
Java HotSpot(TM) 64-Bit Server VM (build 1.9.0-ea-b50, mixed mode)
Congratulation’s! You have successfully installed Java. Thanks for using this tutorial for installing Oracle Java (JDK) 9 on Ubuntu 15.04 system. For additional help or useful information, we recommend you to check the official Java web site.