How To Install Java on AlmaLinux 9

In this tutorial, we will show you how to install Java on AlmaLinux 9. For those of you who didn’t know, Java is a cross-platform, object-oriented, and multipurpose programming language that is primarily used for creating mobile, web, and cloud applications. Java was developed by Sun Microsystems (which is now the subsidiary of Oracle) in the year 1995.

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 the Java programming language on AlmaLinux 9. You can follow the same instructions for CentOS and Rocky Linux.

Prerequisites

• A server running one of the following operating systems: AlmaLinux 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 AlmaLinux 9

Step 1. First, let’s start by ensuring your system is up-to-date.

sudo dnf clean all
sudo dnf update
sudo dnf groupinstall "Development Tools"

Step 2. Installing Java on AlmaLinux 9.

• Install OpenJDK 18 on AlmaLinux 9.

By default, OpenJDK is not available on the AlmaLinux 9 base repository. Now download the OpenJDK installer by running the following command:

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

Extract the downloaded archive using the following command:

tar xvf openjdk-18.0.2_linux-x64_bin.tar.gz
sudo mv jdk-18.0.2 /opt/

Next, 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

Now check the java command and source your profile file:

source /etc/profile.d/jdk18.sh

Verify the OpenJDK installation:

echo $JAVA_HOME

• Install Java SE Development Kit on AlmaLinux 9.

By default, Java SE Development Kit is not available on the AlmaLinux 9 base repository. Now download the Java SE Development Kit package by running the following command:

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

After installing, verify it by running the following command in your terminal window:

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

Finally, use the file below to use Java Home:

source /etc/profile.d/jdk18.sh

Step 3. Managing Multiple Versions of Java.

If you have multiple versions of Java, you can use the update-alternatives command to configure the desired version:

sudo alternatives --config java

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