When I attempt to Generate Signed App Bundle / APK... of my perfectly building and running app, I get the following error:
Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in missing_rules.txt
The file missing_rules.txt only contains the following:
# Please add these rules to your existing keep rules in order to suppress warnings.
# This is generated automatically by the Android Gradle plugin.
-dontwarn lombok.NonNull
But when I add exactly what’s specified in missing_rules.txt, I keep getting the same error. This error keeps occurring even when I add to my proguard.cfg the following:
-dontwarn lombok.**
-keepattributes *Annotation*
My build.gradle contains the required:
compileOnly 'org.projectlombok:lombok:1.18.36'
annotationProcessor 'org.projectlombok:lombok:1.18.36'
So why am I still getting this error?
Note: I ran ..gradlew dependencies and verified that Lombok appears under compileOnly and annotationProcessor only.
At this point, I am out of ideas. I would appreciate any tip that could help me get past this unexpected hurdle.
My Gradle environment:
------------------------------------------------------------
Gradle 8.9
------------------------------------------------------------
Build time: 2024-07-11 14:37:41 UTC
Revision: d536ef36a19186ccc596d8817123e5445f30fef8
Kotlin: 1.9.23
Groovy: 3.0.21
Ant: Apache Ant(TM) version 1.10.13 compiled on January 4 2023
Launcher JVM: 21.0.3 (JetBrains s.r.o. 21.0.3+-12282718-b509.11)
Daemon JVM: C:Program FilesAndroidAndroid Studiojbr (no JDK specified, using current Java home)
OS: Windows 10 10.0 amd64
Android Gradle Plugin Version: 8.7.3
Answering my own question, for the benefit of others who may be baffled by this seemingly mysterious problem:
I solved this problem by simply placing
-dontwarn lombok.NonNull
in the proguard.cfg of the app’s module, not the library module.
Explanation: My app is made of an app module and a library module. The library module is the one that actually uses Lombok’s NonNull annotation, so I thought that the library’s proguard.cfgis the one that should contain the -dontwarn lombok.NonNull directive.
I was wrong: It’s the other way around.
1