How to fix ClassNotFoundException: kotlinx.coroutines.debug.AgentPremain in debug?

Question

I am running several projects as spring boot applications, one of them specifically cannot start and is throwing:

java.lang.ClassNotFoundException: kotlinx.coroutines.debug.AgentPremain
    at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
    at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:304)
    at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:401)
Exception in thread "main" FATAL ERROR in native method: processing of -javaagent failed
Disconnected from the target VM, address: '127.0.0.1:64279', transport: 'socket'

Process finished with exit code 1

The command line has the option:

-javaagent:[...].m2/repository/org/jetbrains/kotlinx/kotlinx-coroutines-core/1.5.0/kotlinx-coroutines-core-1.5.0.jar

And this jar exists.

this happened after updating my Intellij'Idea to 2021.2

This issue happens only in debug mode.

Any idea how to solve this?

Answer 1

It is a known problem in the Kotlin plugin. As a workaround disable the coroutine agent option under Settings/Preferences | Build, Execution, Deployment | Debugger | Data Views | Kotlin | enable "Disable coroutine agent".

Please follow https://youtrack.jetbrains.com/issue/KTIJ-19345 , for updates.