OpenJDK announced the latest JDK 24 yesterday. This is the beginner’s guide shows how to install it in all current Ubuntu and Linux Mint releases.
OpenJDK 24 is a short term release with 6 months support. Ubuntu has made JDK 24 into system repository for upcoming Ubuntu 25.04, while all current Ubuntu releases may use the official tarball instead.
image from oracle.com
Ubuntu developers provide updates for the long term support (LTS) OpenJDK releases (e.g., JDK 8, JDK 17, and JDK 21). Users can install them simply by running a single command in terminal.
For example, you may install OpenJDK 21 in all current Ubuntu releases by running the single command below in terminal:
sudo apt install openjdk-21-jdk
While you may replace 21 with 17 or 8 for other JDK LTS releases.
For non-LTS releases, they also maintains a restricted PPA that contains the most recent OpenJDK for all current Ubuntu releases. However, it’s not updated for JDK 24 at the moment of writing.
Difference between OpenJDK and Oracle JDK
OpenJDK and Oracle JDK are “same thing”, but with different licence.
Oracle JDK is built from the OpenJDK JDK source, but non-opensource licence. While both OpenJDK source and the OpenJDK builds binaries are distributed under the same GPL2+CPE licence.
Both are free! Though, Oracle also offers a subscription for the Oracle JDK builds that user can buy for support! And, I’ve written about how to install Oracle Java 21/24 in Ubuntu.
Install OpenJDK JDK 24:
NOTE: The steps below will override Oracle JDK 24 if installed.
1. To install the new OpenJDK JDK 24, first go to java website via the link below:
Then select download the “Linux / x64” build for AMD/Intel platform, or “Linux / AArch64” for ARM devices (e.g., Raspberry Pi).
2. After downloaded the Linux tarball, press Ctrl+Alt+T to open up a terminal window, and run commands below to extract to /usr/lib/jvm directory.
- First, create the target directory in case this is the first time you install Java on the system.
sudo mkdir -p /usr/lib/jvm
- Then, run command to extract OpenJDK 24 tarball into that directory:
sudo tar -zxf ~/Downloads/openjdk-24_linux-*_bin.tar.gz -C /usr/lib/jvm/
Here assume you saved the tarball in user Downloads folder.
After that, run ls /usr/lib/jvm/ to list directory content. It should include a new jdk-24 (or jdk-24.0.1, jdk-24.0.2, etc) sub-folder.
3. Set OpenJDK JDK 24 as default.
To set it as default, first run commands below one by one to link executable files as alternatives:
sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-24/bin/java 1
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-24/bin/javac 1
sudo update-alternatives --install /usr/bin/jar jar /usr/lib/jvm/jdk-24/bin/jar 1
As you see in the screenshot below, there are many other executable files under /usr/lib/jvm/jdk-24/bin (e.g., javap, jdb, jfr, and more). You may run similar commands above for them one by one as you need.
NOTE: As time goes on, OpenJDK may release updates for JDK 24. In the case, you’ll need to replace “jdk-24” in command with “jdk-24.0.1” or “jdk-24.0.2” according to the Java root folder name under “/usr/lib/jvm”.
After that, run the commands below one by one to choose default Java:
sudo update-alternatives --config java
sudo update-alternatives --config javac
sudo update-alternatives --config jar
Also run similar command above for other executable files if you created links for them.
4. Finally, run command to check the default Java edition:
java --version
javac --version
And, use java -XshowSettings:properties -version to print more the properties.
Uninstall OpenJDK JDK 24
To uninstall OpenJDK JDK 24 installed via the steps above, simply open terminal (Ctrl+Alt+T) and run command to remove the Java folder under /usr/lib/jvm:
sudo rm -R /usr/lib/jvm/jdk-24
Then, remove the alternative links:
sudo update-alternatives --remove java /usr/lib/jvm/jdk-24/bin/java
sudo update-alternatives --remove javac /usr/lib/jvm/jdk-24/bin/javac
sudo update-alternatives --remove jar /usr/lib/jvm/jdk-24/bin/jar
Also run similar command above for other executable files if added. And, replace jdk-24 with jdk-24.0.1 etc. for point releases.
