How to Install Oracle JDK 9 on Debian 9 Stretch Easy Guide

January 18, 2018 | By the+gnu+linux+evangelist.

Oracle JDK 9 Install Debian 9 Stretch

Hello Debian 9 Stretch User! The Tutorial shows you Step-by-Step How to Download and Install Oracle JDK 9 on Debian 9 Stretch GNU/Linux Desktops.

And to SetUp Oracle JDK for Debian 9 Stretch you will need to Use the update-alternatives Tool to Update your System Java to 1.9 JDK9.

Moreover, Java SE 9 includes much awaited New Features like the Modularization of the Java Platform, Better Performance, Support for New Standards, and many other improvements.

The Powerful Java 9 New Features:.

Java REPL Shell jshell
Full support for HTTP 2.0, new HTTP client that implement HTTP 2.0 and websockets
Java Microbenchmarking Harness
Java Process API Boost
Debugging in Production

The Contents and Details of Oracle JDK 9 on Debian 9 Stretch Install are Expressly Minimal to Give Focus Only to the Essentials Instructions and Commands and Make the Tut Easier to Understand ;)

Open a Shell Terminal emulator window
Start Typing ‘term’ on Desktop.
(Press “Enter” to Execute Commands)

In case first see: Terminal QuickStart Guide.
Download Oracle Java SE JDK 9 for Linux.

Oracle JDK 9 Linux tar.gz

Oracle JDK 9
Double-Click on the tar.gz Archive and Extract into /tmp
Or from Shell:
```
tar xvzf ~/Downloads/jdk-9*.tar.gz -C /tmp/
```
Relocate Java JDK 9.
```
su -
```
If Got “User is Not in Sudoers file” then see: How to Enable sudo
Make a jvm Directory if Not already there with
```
if [ ! -d "/usr/lib/jvm" ]; then mkdir /usr/lib/jvm; fi
```
Set the root superUser as owner:
```
sudo chown -R root:root /tmp/jdk-9
```
Reiterate the Execution Permission over the Java binaries:
```
chmod -R +x /tmp/jdk-9/bin
```
Finally, Shift the Java contents with:
```
mv /tmp/jdk-9 /usr/lib/jvm/
```

Installing Oracle Java JDK 9
You can directly Copy & Paste the Commands into Terminal..

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-9/bin/java 1065

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-9/bin/javac 1065

update-alternatives --install /usr/bin/jar jar /usr/lib/jvm/jdk-9/bin/jar 1065

update-alternatives --install /usr/bin/javaws javaws /usr/lib/jvm/jdk-9/bin/javaws 1065

Checking or Setting the System Java Version in Use with

update-alternatives --config java

And for the Java Compiler instead:

sudo update-alternatives --config javac

To Switch of Java Version Just Enter the Selection Number on First, Column. :)

(Optional) Setting JAVA_HOME User Environment Variable.
```
su [myUserName]
```
Or simply:
```
exit
```
And Edit the Bash environment Configuration file
```
nano $HOME/.bashrc
```
Append:
```
export JAVA_HOME=/usr/lib/jvm/jdk-9
```
Possibly to Check the JDK 9 exact PATH use in another window:
```
ls /usr/lib/jvm/
```
Ctr+x to Save & Exit from nano Editor :)
Next to Load the New Bash Environment:
```
bash
```
Finally, Test New Java JDK 9 Installation.
```
java -version
```

Java IDEs Installation on Debian 9 Stretch

Eclipse IDE for Java Development Install on Debian 9 Stretch: Installing Eclipse IDE for Java Dev on Debian 9 Stretch.

Netbeans IDE for Java Development Install on Debian 9 Stretch: Installing NetBeans IDE for Java Dev on Debian 9 Stretch.

IntelliJ IDEA 2024 for Java Development Install on Debian 9 Stretch: Installing IntelliJ IDEA for Java Dev on Debian 9 Stretch.

Now Thanks to Oracle-Sun Corporation you are able to Successfully Start Up with Java 9 Development.

Welcome to Java 9 New Dev Env! ;)