Java JDK is a widely-used programming language, known for its versatility and compatibility across various applications. Keeping Java up-to-date on your Red Hat Enterprise Linux (RHEL), CentOS, Fedora, AlmaLinux, Rocky, Oracle or Linux-based operating system is crucial for security and performance reasons. In this article, I will explain to you all how to install and configure Java JDK latest version on RPM based Linux operating system.

     Operating System: Fedora Linux 37 (Workstation Edition)
     Kernel: Linux 6.5.5-100.fc37.x86_64
     Architecture: x86-64

Two Method to download and Install

1: Through yum repository

2: Through Linux Binaries

Method 1: Install Java JDK through yum utility

Before installing Java via the YUM repository, it’s important to start by searching for and inspecting the available information using a Yum or dnf tool. This information will show which version of Java will be installed through the ‘java-latest-openjdk’ package. Subsequently, you can access the Java RPM package in the application stream repository and utilize either the ‘dnf’ or ‘yum’ command in a Linux environment for installation.”

# dnf search openjdk 

Now list and install the latest version of Java install.

# dnf list java-latest-openjdk 
# dnf info java-latest-openjdk 
# dnf install java-latest-openjdk 

In the ‘dnf search’ results, you will find various available versions of the JDK. If you have a specific version in mind that you wish to install, simply choose the name of that particular version from the list and proceed with the installation.

To verify the installation, you can execute the below command :

# java --version 
openjdk 21 2023-09-19
OpenJDK Runtime Environment (Red_Hat- (build 21+35)
OpenJDK 64-Bit Server VM (Red_Hat- (build 21+35, mixed mode, sharing)

Set Default Java jdk Version :

If you have installed different Java versions installed on your Linux system, you can set the default Java version using the alternatives command. This will allow you to switch between different Java versions easily.

To list the installed Java versions, use:

# alternatives --list 

To set a default Java version, use:

# alternatives -config java 

Method 2: Download & Install Java JDK through Linux Binary

Download the latest  Java SE  Development Kit from its official Java vendor website. Below are the steps to extract and download JDK files in a temporary folder in Linux. You have to download the tar archive file. We downloaded the JDK file in our temp folder. We will go into the /tmp folder and extract it there.

OpenJDK JDK binaries are available for Linux on as compressed zip or tar.gz archives.

# cd /tmp
# wget 
# tar xzf jdk-21_linux-x64_bin.tar.gz
# mv jdk-21  /opt

Install  Java 21

Now we have got extracted folder of Java. The alternatives command is the best way to install Java. Go to the extracted folder of Java and run like below command as shown.

# cd /opt/jdk-21

# alternatives --install /usr/bin/java java /opt/jdk-21/bin/java 2 

Now we should set the jar and javac  path

# alternatives --install /usr/bin/jar jar /opt/jdk-21/bin/jar 2

# alternatives --install /usr/bin/javac javac /opt/jdk-21/bin/javac 2

# alternatives --install /usr/bin/javac javac /opt/jdk-21/bin/javac 2

# alternatives --set javac /opt/jdk-21/bin/javac

Set  Java Environment Variables :

After the set of Javac and JRE paths, we will set the environment variables in Linux. Many application needs to use the JAVA_Home or JRE_HOME environment variables for the Java executable to use.

Set the java jdk home variable using the below command.

export JAVA_HOME=/opt/jdk-21

Path set  jre home variable use below command

export JRE_HOME=/opt/jdk-21/jre/

Setting the path variables use the below command

export PATH=$PATH:/opt/jdk-21/bin:/opt/jdk-21/jre/bin

Verify Installed Java JDK Version

Now check the version of installed Java on the Linux box through the below command

java 21 2023-09-19 LTS
Java(TM) SE Runtime Environment (build 21+35-LTS-2513)
Java HotSpot(TM) 64-Bit Server VM (build 21+35-LTS-2513, mixed mode, sharing)

if the java command not running after setting the environment variables, you can add the below lines in bashrc and profile files in the /etc directory.

export JRE_HOME=/opt/jdk-21/jre
export PATH=$JAVA_HOME/bin:$PATH

Congratulations, Now we have installed, run, and configured Java!

By Sachin G

I am a professional freelance contributor and founder of tech transit. Love to write and lover of education, culture, and community. I have been using it, setting, supporting, and maintaining it since 2009.Linux rocks! Sachin G Follow me on LinkedIn and x formerly twitter