Thanks for starting the thread, Jesse. I think this is a great idea for Druid 38. Is there any place you have in mind where you are eager leverage Java 21 language features? A good motivation to share with the change notice helps communicate the benefit of updating our Java support matrix. Regardless, I’m on board with it.
Regarding java25, is that your analysis from initial inspection the Hadoop docs/code or did you smoke check the compatibility at runtime too? Thanks, Lucas On Tue, Apr 14, 2026 at 12:08 AM Jesse Tuğlu <[email protected]> wrote: > Hi folks, > > Wanted to start a devlist thread to discuss removal of JDK 17 in favor of > JDK 21/25 as supported runtimes in Druid 38. The PR for this change is > here: https://github.com/apache/druid/pull/19304. Upgrading to Hadoop 3.5 > clients enabled <https://hadoop.apache.org/docs/r3.5.0/> the use of JDK 21 > and, from what I can tell, contains SecurityManager patches that unblock > Druid's usage of JDK 25. > > Best, > > Jesse >
