Install Java 9 on Windows

This tutorial will show how to install Java 9 on Windows and set up the necessary environment variables for application development.

Download

Visit this link to download the appropriate JDK 9 for your Windows, accepting Oracle’s license agreement.

Installation

Run the downloaded installer and proceed with the installation, accepting the licence terms and advancing the installation steps to complete the process, without any additional settings as the following screenshots:

Environment Variables

Open the environment variables settings window by pressing Windows + Pause/Break or through Control Panel -> System -> Advanced system settings -> Environment Variables.

Click on New… button on System environment variables and add the three following variables.

Variable name	Variable value
JAVA_HOME	JDK installation path, example: C:\Program Files\Java\jdk-9
CLASSPATH	. (just a dot)
PATH	It may already exists on your system under the name Path, so edit its value by adding at the end: %JAVA_HOME%\bin; If it not exists already, create a new one with the value %JAVA_HOME%\bin;

Validating

In order to validate the Java installation and the environment variables setup, open the Command Prompt by clicking the Start Menu and type cmd. Next, type the following commands in the prompt, which should print the version information if Java has been configured correctly.

C:\Users\Bruno>java -version
java version "9"
Java(TM) SE Runtime Environment (build 9+181)
Java HotSpot(TM) 64-Bit Server VM (build 9+181, mixed mode)

C:\Users\Bruno>javac -version
javac 9

I hope it helps.
Cya!