IntelliJ Maven Not Resolving Dependencies / Not Applying Excludes

I recently had a ton of issues with dependencies in IntelliJ with maven, on multiple consecutive occasions. This is pretty odd as I’ve used IntelliJ and Maven for probably around 10 years (I even have the top youtube videos on that combination!).

I’m on IntelliJ 2020.1 currently, and I found a few things through painful trial and error here. I hope they help you.

  1. Apparently at some point they removed that “Automatically Import” option that used to pop up when you created/imported a maven project. This used to make things automatically resolve as you changed your POM. Now you need to make sure you build to pull in dependencies, and for safe measure I also click the “re-import” button on the maven tools tab (little icon at the top row).
  2. There is now an “offline” mode. So, you may keep failing and failing to install because you can’t resolve dependencies on, say, maven central. This is super confusing as you may actually be online and looking at maven central and seeing the dependencies there. If this happens, check/disable offline mode!
  3. You may add excludes to a complex dependency (like the hive metastore in my case) to remove transitive dependencies that break your app/framework (like spring boot). You shold make sure to change the POM, clean, and then re-import the maven project again to ensure they’re really gone. I kept seeing them in the external dependencies list in the object browser, and my builds were failing, until I did the last step of re-importing.
  4. If all else fails, clean, invalidate-and-restart (in the file menu), install, and re-import and it seems to be a good catch-all for when you’re completely lost.

This all seems pretty crazy to me, but I’ve gone through it a few times now and it seems right. I hope it helps you save some of the time I wasted!