Kotlinx.coroutines: java.lang.ClassNotFoundException: kotlin.coroutines.jvm.internal.CoroutineImpl

[li-xiaojun]

my build.gradle:

buildscript {
    ext.kotlin_version = '1.3.0-rc-190'
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}
apply plugin: "kotlin"
group 'com.lxj'
version '1.0-SNAPSHOT'

sourceCompatibility = 1.8

repositories {
    mavenCentral()
}
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${kotlin_version}"
    testCompile group: 'junit', name: 'junit', version: '4.12'
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.0.0-RC1'
}
compileKotlin {
    kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}

my code is:

fun main(args: Array<String>) {

    GlobalScope.launch{
        print("I am from coroutines")
    }
}

the console output:

Exception in thread "main" java.lang.NoClassDefFoundError: kotlin/coroutines/jvm/internal/CoroutineImpl
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at start.AKt.main(a.kt:13)
Caused by: java.lang.ClassNotFoundException: kotlin.coroutines.jvm.internal.CoroutineImpl
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 13 more

[qwwdfsad]

Is it still a problem with corouines 1.0.0 and Kotlin 1.3?

[EvilBT]

@qwwdfsad yes.

[qwwdfsad]

Could you please provide a sample project which reproduces the problem?

I've created a project with the same build.gradle (but with version 1.3 and 1.0.0) and it works properly

[tustar]

Same issue

import kotlinx.coroutines.GlobalScope
import kotlinx.coroutines.launch


fun main(args: Array<String>)  {
    GlobalScope.launch { // launch new coroutine in background and continue
//        delay(1000L) // non-blocking delay for 1 second (default time unit is ms)
        println("World!") // print after delay
    }
    println("Hello,") // main thread continues while coroutine is delayed
    Thread.sleep(2000L) // block main thread for 2 seconds to keep JVM alive
}

[li-xiaojun]

it works after I update IDEA kotlin plugin to 1.3 and restart IDEA，before the plugin version is 1.2.65.

[tustar]

@li-xiaojun , It works for me, thanks!

[Nadim96]

Updating kotlin to 1.3 and restarting gave me another error (using the quickstart code on https://ktor.io/quickstart/index.html).

adding

implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.0.0-RC1'
to

dependencies {
}

fixed it for me

[dtschmidt]

@Nadim96 that fixed it for me as well! I should have thought of that but I'm so glad to have found your comment. Thank you!

[kid1412621]

got this error when using spring webflux corouter (added implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.2")
in gradle)