OjWej, what have I done wrong this time? :cry: ```java.lang.NoClassDefFoundError: kotlin/coroutines/...

# coroutines

[Alexander Schell]

OjWej, what have I done wrong this time? 😢

java.lang.NoClassDefFoundError: kotlin/coroutines/AbstractCoroutineContextKey

I thought adding kotlinx-coroutines-core to my pom.xml would be enough...?

kotlin: 1.3.72
kotlinx-coroutines-core: 1.3.7 - Also tried it with 1.3.5: Same result...

[gildor]

looks that you don’t have stdlib (or your stdblib is too old)

[Alexander Schell]

Hello Andrey
I'm using kotlin-stdlib-jdk8 in version 1.3.72. Will chekc if there is a more recent version.
Thanks!
Best regards
Alex

[gildor]

no 1.3.72 should be enough

[gildor]

maybe you have something like old kotlin-stdlib (which overrides jdk8 transitive dependecy)

[gildor]

kotlin-stdlib-jdk8 itself is a very small artifact which provides a few classes for Java 8 support, but it itself has kotlin-stdlib in dependencies

[gildor]

also, check that you don’t have kotlin-stdlib-jre8 this is old name of the same artifact which existed before Kotlin 1.2, so it may also bring old stdlib to classpath and I not sure how maven dependency resolution will work in this case

[Alexander Schell]

Hello Andrey
Thanks for your help but just foget it: I'm as dumb as I'm tall... 🤪
I've fogotten to include kotlin-stdlib in my dependency-list...
How embarrassing... 🙁
Best regards
Alex

[gildor]

kotlin-stdlib should be transitively added by kotlin-stdlib-jdk8, but again not very familiar with maven

[Alexander Schell]

Yes, that's what puzzles me a little bit: The transitively added dependencies should be added to the class-path.
I've added the dependency to my pom.xml explicitly now. And - Surprise! - it works like expected. Funny.

[gildor]

That what I’m saying, maybe it was overwritten by another depedency, because in maven not always the nevest version is used (at least as I know), dependency resolution is different