How to Install Java on Ubuntu 26.04

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Java logo and Ubuntu branding for the Ubuntu 26.04 installation guide

Java is a popular programming language used for building applications and software solutions. It runs on all major operating systems and devices.

This guide covers installing OpenJDK and Oracle JDK on Ubuntu 26.04.

Quick Reference

TaskCommand
Install default JDKsudo apt install default-jdk
Install OpenJDK 21sudo apt install openjdk-21-jdk
Install OpenJDK 25sudo apt install openjdk-25-jdk
Check Java versionjava -version
Change default Javasudo update-alternatives --config java
Set JAVA_HOMEAdd to /etc/environment
Uninstall Javasudo apt remove openjdk-25-jdk

Before You Begin

There are several Java implementations available. OpenJDK and Oracle JDK are the two most common choices. OpenJDK is the default option in Ubuntu and the best fit for most systems.

Ubuntu 26.04 includes OpenJDK packages for both the Java Runtime Environment (JRE) and the Java Development Kit (JDK). The JRE includes the Java virtual machine (JVM) and the libraries needed to run Java programs. The JDK includes the JRE plus the tools needed to build Java applications.

If you are not sure which package to install, start with the default OpenJDK version. Some applications require a specific Java release, so check the application documentation before you install it.

Installing OpenJDK in Ubuntu

Check if Java is already installed:

Terminal
java -version

If Java is not installed, the output will tell you the command is not found. Otherwise, it shows the installed version.

Update the package index:

Terminal
sudo apt update

The current long-term supported (LTS) versions of Java are: 11, 17, 21, and 25. The default Java in Ubuntu 26.04 is Java 25, which you get by installing the default-jdk package.

Install latest LTS Java 25:

Terminal
sudo apt install openjdk-25-jdk
Info
If you want to install another version, replace the version number. For example, if your application requires Java 21, install the openjdk-21-jdk package.

Verify the installation:

Terminal
java -version
output
openjdk version "25.0.3-ea" 2026-04-21
OpenJDK Runtime Environment (build 25.0.3-ea+7-Ubuntu-2)
OpenJDK 64-Bit Server VM (build 25.0.3-ea+7-Ubuntu-2, mixed mode, sharing)

JRE is included in the JDK package. If you need only JRE, install the openjdk-25-jre package. For minimal Java runtime, install the openjdk-**25**-jre-headless package.

Installing Oracle Java in Ubuntu

Oracle JDK is not available in the default Ubuntu repositories. You can install it by downloading the .deb package from Oracle.

At the time of writing, Oracle’s downloads page offers both JDK 26, the latest feature release, and JDK 25, the latest LTS release. Oracle JDK 25 is available under Oracle No-Fee Terms and Conditions (NFTC), which allows free production use and redistribution for that release. If you plan to standardize on Oracle JDK, review Oracle’s current licensing terms before deployment.

Visit the Oracle Java Downloads page and select the version you need.

In this example, we will download and install Java 25 because it is the current LTS release. If you want the newest feature release instead, download JDK 26 from the same page. Choose the Linux x64 Debian Package for the version you want and download the .deb file.

java 25

If you are installing on a server, use wget to download the file:

Terminal
wget https://download.oracle.com/java/25/latest/jdk-25_linux-x64_bin.deb

Install the package:

Terminal
sudo apt install ./jdk-25_linux-x64_bin.deb

Replace the filename if you downloaded a different version.

Setting the Default Java Version

If you have multiple Java versions installed, check the current default:

Terminal
java -version

Change the default version with update-alternatives:

Terminal
sudo update-alternatives --config java

You will see a list of installed Java versions:

output
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                         Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/jdk-25.0.3-oracle-x64/bin/java   419454976 auto mode
  1            /usr/lib/jvm/java-25-openjdk-amd64/bin/java   2511      manual mode
  2            /usr/lib/jvm/jdk-25.0.3-oracle-x64/bin/java   419454976 manual mode

Press <enter> to keep the current choice[*], or type selection number: 

Enter the number of the version you want as default and press Enter.

Verify the change:

Terminal
java -version

Setting the JAVA_HOME Environment Variable

Some Java applications use the JAVA_HOME environment variable to determine the JDK location.

First, find the Java installation path:

Terminal
sudo update-alternatives --config java

The paths are:

  • Oracle JDK 25 is located at /usr/lib/jvm/jdk-25-oracle-x64/bin/java
  • OpenJDK 25 is located at /usr/lib/jvm/java-25-openjdk-amd64/bin/java
Info
The java binary is located at JAVA_HOME/bin/java. Set JAVA_HOME to the path above, excluding the bin/java part.

Open the /etc/environment file:

Terminal
sudo nano /etc/environment

Add the following line (adjust the path for your preferred version):

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

Apply the changes:

Terminal
source /etc/environment

Verify the variable is set:

Terminal
echo $JAVA_HOME
output
/usr/lib/jvm/java-25-openjdk-amd64
Info
/etc/environment is system-wide. To set JAVA_HOME per user, add the line to .bashrc or another shell configuration file.

Uninstalling Java

Uninstall Java like any other package:

Terminal
sudo apt remove openjdk-25-jdk

Replace the package name with the version you want to remove.

Conclusion

We covered installing OpenJDK from the Ubuntu 26.04 repositories and downloading Oracle JDK manually. The default OpenJDK 25 works for most applications, but Java 26 is also available in the Oracle repositories for the latest features.

For more information, see the official OpenJDK documentation .

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About the authors

Dejan Panovski

Dejan Panovski

Dejan Panovski is the founder of Linuxize, an RHCSA-certified Linux system administrator and DevOps engineer based in Skopje, Macedonia. Author of 800+ Linux tutorials with 20+ years of experience turning complex Linux tasks into clear, reliable guides.

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