How To Install Java on Rocky Linux 9

In this tutorial, we will show you how to install Java on Rocky Linux 9. For those of you who didn’t know, Java is a popular programming language and software platform that allows you to run many server-side applications. The general purpose of the Java programming language is to let developers write programs or applications once, but the application itself can be run on any system across multiple operating systems.

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 and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of Java programming language on Rocky Linux. 9.

Prerequisites

• A server running one of the following operating systems: Rocky Linux 9.
• It’s recommended that you use a fresh OS install to prevent any potential issues.
• SSH access to the server (or just open Terminal if you’re on a desktop).
• A non-root sudo user or access to the root user. We recommend acting as a non-root sudo user, however, as you can harm your system if you’re not careful when acting as the root.

Install Java on Rocky Linux 9

Step 1. The first step is to update your system to the latest version of the package list. To do so, run the following commands:

sudo dnf makecache --refresh
sudo dnf install dnf-utils

Step 2. Installing OpenJDK on Rocky Linux 9.

• Install OpenJDK 18 on Rocky Linux.

By default, OpenJDK is not available on Rocky Linux 9 base repository. Now run the following command below to download the latest stable version of OpenJDK to your system:

wget https://download.java.net/java/GA/jdk18.0.2/f6ad4b4450fd4d298113270ec84f30ee/9/GPL/openjdk-18.0.2_linux-x64_bin.tar.gz

Next, extract the downloaded archive:

tar xvf openjdk-18.0.2_linux-x64_bin.tar.gz

Move the extracted folder to the /opt directory:

sudo mv jdk-18.0.2 /opt/

Then, configure the Java environment:

sudo tee /etc/profile.d/jdk18.sh <<EOF
export JAVA_HOME=/opt/jdk-18
export PATH=\$PATH:\$JAVA_HOME/bin
EOF

After that, we check the java command and source your profile file:

source /etc/profile.d/jdk18.sh

If all installation is completed, verify your Java OpenJDK version using the following command:

java -version

• Install Java SE Development Kit 18 on Rocky Linux.

By default, Java SE Development Kit is not available on Rocky Linux 9 base repository. Now run the following command below to download the latest stable version of Java SE Development Kit to your system:

wget https://download.oracle.com/java/18/latest/jdk-18_linux-x64_bin.rpm

Next, install the downloaded package using the following command:

sudo rpm -Uvh jdk-18_linux-x64_bin.rpm

Use the following command to check whether Java is installed:

java -version

Next, configure the Java environment:

cat <<EOF | sudo tee /etc/profile.d/jdk18.sh
export JAVA_HOME=/usr/java/default
export PATH=\$PATH:\$JAVA_HOME/bin
EOF

Use the file below to use Java Home:

source /etc/profile.d/jdk18.sh

Step 3. Managing Multiple Versions of Java.

Now, you will learn how to switch to a different java version the Rocky Linux using the command ‘alternatives‘:

sudo alternatives --config java

Congratulations! You have successfully installed java. Thanks for using this tutorial for installing the Java programming language on your Rocky Linux 9 system. For additional help or useful information, we recommend you check the official Java website.