After upgrading Ktor to 2 0 0 I see this error in IntelliJ o

Question

After upgrading Ktor to 2 0 0 I see this error in IntelliJ only no error when building from gradle ```Cannot access class kotlinx serialization json Json Check your module classpath for missing or conflicting dependencies``` when I try to use content negotiation ``` install ContentNegotiation json json ``` I checked the dependencies but I can t see any obvious conflicts

Robert Jaros · Answer

I see also this error ```Cannot access class kotlinx coroutines channels ReceiveChannel Check your module classpath for missing or conflicting dependencies``` in the same module when using websockets and channels

simon.vergauwen · Answer

Did you include `io ktor ktor serialization kotlinx json` as a dependency

Robert Jaros · Answer

Yes

Robert Jaros · Answer

The project is building from gradle and is working fine with new Ktor The errors are only in IntelliJ

simon.vergauwen · Answer

Oh in that case you might want to try refreshing Gradle inside IntelliJ `cmd+shift+a` gt `Refresh Gradle Dependencies` That triggers IntelliJ to rescan and index the dependencies again so it might correctly resolve the code after that

Robert Jaros · Answer

Unfortunately it didn t help

simon.vergauwen · Answer

Strange this is working for me on Ktor 2 0 with KotlinX Serialization for server

simon.vergauwen · Answer

simon.vergauwen · Answer

Here is the configuration of Ktor <https github com nomisRev ktor arrow example blob main src main kotlin io github nomisrev config ktor kt>

simon.vergauwen · Answer

I have an `api` dependency on KotlinX Coroutines through Arrow Fx Coroutines though and KotlinX Serialization Gradle Plugin adds a dependency to KotlinX Seriliaziation Core

Robert Jaros · Answer

I see a lot more other errors in IntelliJ as I check different files in my project All of them are about serialization coroutines incompatibility or accessibility and not all are Ktor specific So I think I have some other general problem with my project and IntelliJ I ll make some more tests with previous Kotlin and Ktor versions

Aleksei Tirman [JB] · Answer

Please try to invalidate caches in IDE

Robert Jaros · Answer

Tried that already doesn t help

Aleksei Tirman [JB] · Answer

Then I can only suggest removing a Gradle cache by deleting ~ gradle and ~ m2 folders

Robert Jaros · Answer

It doesn t seem like a cache problem I have found a different project with similar error

Robert Jaros · Answer

I can fix this error by changing one dependency in common module from `api` type to `implementation` type

Robert Jaros · Answer

When I go back to `api` the error is back as well

Robert Jaros · Answer

It s a Ktor project with `implementation io ktor ktor server core $ktorVersion ` dependecy in `jvmMain` source set so coroutines version 1 6 0 is on the classpath

Robert Jaros · Answer

It works fine from gradle as well just this error in IntelliJ

Robert Jaros · Answer

adding `api org jetbrains kotlinx kotlinx coroutines core 1 6 0 ` in common source set dosn t fix the problem but `implementation org jetbrains kotlinx kotlinx coroutines core 1 6 0 ` does fix the problem

Robert Jaros · Answer

It s a bit crazy wink

Aleksei Tirman [JB] · Answer

This is most likely <https youtrack jetbrains com issue KT 49877|it>

Robert Jaros · Answer

Thanks It does look similar