Issue with Caffeine integration

[Yomanz]

WARNING: Exception thrown by stats counter
java.lang.IllegalAccessError: class kamon.instrumentation.caffeine.KamonStatsCounter tried to access private method 'void com.github.benmanes.caffeine.cache.stats.CacheStats.<init>(long, long, long, long, long, long, long)' (kamon.instrumentation.caffeine.KamonStatsCounter and com.github.benmanes.caffeine.cache.stats.CacheStats are in unnamed module of loader 'app')
	at kamon.instrumentation.caffeine.KamonStatsCounter.snapshot(KamonStatsCounter.scala:46)
	at com.github.benmanes.caffeine.cache.stats.GuardedStatsCounter.snapshot(GuardedStatsCounter.java:90)
	at com.github.benmanes.caffeine.cache.LocalAsyncCache$AbstractCacheView.stats(LocalAsyncCache.java:569)

(Image of the private method)

I am getting this exception thrown when using kamon and caffeine together, specifically I am using Akka HTTP Prometheus metrics package which seems to be automatically hooked into by kamon.

I can provide any extra additional information as required

[ivantopo]

Hey @Yomanz, can you please share what exact Kamon/Caffeine/Java versions are you using here? Thanks!

[Yomanz]

Hey @Yomanz, can you please share what exact Kamon/Caffeine/Java versions are you using here? Thanks!

Absolutely!

Java: Corretto 17 (Scala 2.13.7)
Kamon: 2.6.0
Caffeine: 3.1.1 (Scaffeine 5.2.1)

[Yomanz]

@ivantopo I've just noticed that Kamon doesn't monitor async caffeine caches, is there a specific reason for this?

[Yomanz]

Hi @ivantopo, are there any updates here?
I can always take a peek at fixing it.