How to Install Java 25 on Ubuntu 26.04 LTS

Learn how to install Java 25 on Ubuntu 26.04 LTS using the official OpenJDK package. Follow this step by step guide to install Java, configure JAVA_HOME, verify the installation, and run your first Java program.

What is Java?

Java is one of the most popular programming languages used to build web applications, desktop software, enterprise applications, and Android apps. If you are planning to develop Java applications or run Java based software, installing the Java Development Kit (JDK) is the right choice.

Ubuntu 26.04 LTS includes OpenJDK 25 as its default Java version. Since Java 25 is the latest Long Term Support (LTS) release, you can install it directly from the official Ubuntu repository without adding any third party repository.

Prerequisites

Before you begin, make sure you have:

A dedicated server or desktop running Ubuntu 26.04 LTS
A user account with sudo privileges
Internet access

Let's start Learning how to install Java 25 on Ubuntu 26.04 LTS using the official OpenJDK package

Step 1: Update the Package List

It is always a good idea to refresh your package list before installing new software.

sudo apt update

Step 2: Install Java 25

Install the latest OpenJDK 25 package by running:

sudo apt install openjdk-25-jdk

Press Y when Ubuntu asks for confirmation.

The installation may take a few minutes depending on your internet connection.

Step 3: Verify the Installation

Once the installation is complete, check the installed Java version.

java -version

You should see output similar to:

openjdk version "25.0.3" 2026-04-21
OpenJDK Runtime Environment (build 25.0.3+9-2-26.04.2-Ubuntu)
OpenJDK 64-Bit Server VM (build 25.0.3+9-2-26.04.2-Ubuntu, mixed mode, sharing)

Next, verify that the Java compiler is also installed.

javac -version

Example output:

javac 25.x.x

If both commands display version 25, Java has been installed successfully.

Step 4: Check the Installed Java Location

If you would like to know where Java is installed, run:

which java

Example output:

/usr/bin/java

To see the actual installation directory, run:

readlink -f /usr/bin/java

Example output:

/usr/lib/jvm/java-25-openjdk-amd64/bin/java

Step 5: Check the JAVA_HOME Path

Many Java applications require the JAVA_HOME environment variable.

To find the Java installation directory, run:

readlink -f $(which java)

The output will look similar to:

/usr/lib/jvm/java-25-openjdk-amd64/bin/java

Your JAVA_HOME path is:

/usr/lib/jvm/java-25-openjdk-amd64

Step 6: Set the JAVA_HOME Environment Variable

Open the environment file.

sudo nano /etc/environment

Add the following line at the end of the file.

JAVA_HOME="/usr/lib/jvm/java-25-openjdk-amd64"

Save the file and exit the editor.

Reload the environment variables.

source /etc/environment

Verify that the variable is available.

echo $JAVA_HOME

Expected output:

/usr/lib/jvm/java-25-openjdk-amd64

Step 7: Create a Simple Java Program

Create a new Java file.

nano HelloWorld.java

Paste the following code.

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

Save the file.

Compile the program.

javac HelloWorld.java

Run the program.

java HelloWorld

Output:

Hello, World!

This confirms that both the Java compiler and runtime are working correctly.

Check the Default Java Version

If you have multiple Java versions installed, you can check which version is currently active.

java -version

You can also list the installed Java versions.

update-java-alternatives --list

If multiple versions are available, select the one you want.

sudo update-alternatives --config java

Choose the number corresponding to Java 25.

Uninstall Java 25

If you no longer need Java 25, remove it with the following command.

sudo apt remove openjdk-25-jdk

To remove packages that are no longer required, run:

sudo apt autoremove

Conclusion

You have successfully installed Java 25 on Ubuntu 26.04 LTS. The installation uses the official Ubuntu repository, making it easy to receive future security updates through the standard package manager. You also verified the installation, configured the JAVA_HOME variable, and tested Java by compiling and running your first program. Since Java 25 is the default LTS release in Ubuntu 26.04, it is a great choice for both development and production environments.