Bug Gradle error when compiling aab: Bee gives "UnityPlayerActivity.java uses or overrides..."

Hi there,
I'm trying to compile an aab with Unity 2021.3 for the android app store. I removed Unity Ads, since the store rejected our build because of it, and then started getting this error with no other change in what I do:

Code (CSharp):

1. Note: C:\Users\mjpg7\Unity Projects\PlaycomicsUnity\playcomicsunity\Library\Bee\Android\Prj\IL2CPP\Gradle\unityLibrary\src\main\java\com\unity3d\player\UnityPlayerActivity.java uses or overrides a deprecated API.
2. Note: Recompile with -Xlint:deprecation for details.

I've seen other threads with similar errors, but none from this specific source. How do I fix this? "Remove Unity Ads" seems to come up a lot, but doing that is what started the problem. Client is going to get pretty peeved if I don't figure it out soon, and I don't understand the "Recompile with..." solution as I'm not using any command line hackery (nor do I want to). Thanks,

 

How to troubleshoot build failures:

First, make a blank project with a single blank scene and prove that it builds successfully.

If the blank project does NOT build, go fix your Unity installation or your other tools, such as Android SDK, NDK, JDK, etc. It may even be necessary to change to a different version of Unity3D. It is generally best to stay with LTS versions of Unity3D.

Until you can build a blank project to the target platform, don't fiddle with anything else.

Once you can build a blank project, now bisect the problem by bringing over parts of your current project and building it one subsystem at a time, perhaps stubbing things out that might trigger compiler errors.

Most often things that prevent building are third-party libraries such as Firebase.

Once you identify the subsystem, go to the documentation for it and make sure you are doing it correctly.

It may also be helpful to work through a tutorial or two for whatever subsystem is making the build fail.

Android build not building:

Recently (circa July 2022) there have been reports of Unity's installer failing to install the Android Tools.

https://forum.unity.com/threads/cant-build-for-android.1306098/

Here was how I brought up Unity2020.3.41 and the Android SDK 31 on October 30, 2022 (edited on August 23, 2023 to include Android SDK 33...):

https://forum.unity.com/threads/aab...y-2021-3-8-with-jdk-1-8.1322211/#post-8551193

Android Gradle errors and other related stuff:

https://forum.unity.com/threads/unity-gradle-bug-please-help.1368018/#post-8625789

 

Okay, looks like deleting the library cache and reopening the build Got rid of the error. I really wish Unity was better at managing its own library state.