Problems on evaluating Kotlin inside JVM with javax.script.ScriptEngineManager

Question

I'm trying to evaluate Kotlin code inside JVM using the Java Scripting API.

try {
    ScriptEngineManager().getEngineByExtension("kts").let {
        it.eval("val f: (CommandContext.()->Any?) = {\n${this.args.joinToString(" ")}\n}; return f") as (CommandContext.()->Any?)
    }().let { embed.setDescription(it.toString()) }
} catch (ex: Exception) {
    embed.setColor(Color.RED)
    embed.setDescription(StringWriter().also { ex.printStackTrace(PrintWriter(it)) }.toString())
}

But... ScriptEngineManager().getEngineByExtension("kts") is returning me a null value. I already added the META-INF/services file:

File Name: javax.script.ScriptEngineFactory

File Content: org.jetbrains.kotlin.script.jsr223.KotlinJsr223JvmLocalScriptEngineFactory

It sould work according to JetBrains: https://github.com/JetBrains/kotlin/tree/master/libraries/examples/kotlin-jsr223-local-example

score 4 · Answer 1 · answered Jun 11 '19 at 14:36

Adding a follow up because I was getting the same error but after getting the dependencies for 1.3.31 and added the script engine initialization file I was able to get it working.

My working dependencies:

plugins {
    base
    kotlin("jvm") version "1.3.31"
}
...

dependencies {
    compile(kotlin("stdlib"))
    compile(kotlin("reflect"))
    compile(kotlin("script-runtime"))
    compile(kotlin("compiler-embeddable"))
    compile(kotlin("script-util"))
    runtime(kotlin("scripting-compiler-embeddable"))

    testImplementation("org.junit.jupiter:junit-jupiter-api:5.2.0")
    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.2.0")

}

You definitely need to add the file src/main/resources/META-INF/services/javax.script.ScriptEngineFactory.

Here is the example file: https://github.com/JetBrains/kotlin/blob/master/libraries/examples/kotlin-jsr223-local-example/src/main/resources/META-INF/services/javax.script.ScriptEngineFactory

This chunk of code should show that you have the kotlin extension registered.

ScriptEngineManager().engineFactories.forEach { println(it.extensions)
...
[kts]
[js]

score 1 · Accepted Answer · edited Jun 10 '19 at 23:49

1

I just fixed by adding

compile 'org.jetbrains.kotlin:kotlin-compiler:1.3.11'
compile 'org.jetbrains.kotlin:kotlin-script-runtime:1.3.11'
compile 'org.jetbrains.kotlin:kotlin-script-util:1.3.11'
compile 'org.jetbrains.kotlin:kotlin-compiler-embeddable:1.3.11'

to my build.gradle.

PS: 1.3.11 is my Kotlin version.

edited Jun 10 '19 at 23:49

Chris Hinshaw

6,967
2
39
65

answered Dec 19 '18 at 05:40

NathanPB

685
1
7
22

1

Also, this didn't work for me with Maven and Kotlin version `1.3.31`. :( – Jezor May 06 '19 at 18:05
tested and compiler not compilern worked for me. Also to be more clear WRT the location of the services file, it goes in ...//src/main/resources/META-INF/services, where ...//src/main/java/... gets you to your .kt source files – AndrewStone May 16 '19 at 02:26

score 0 · Answer 3 · answered Apr 06 '21 at 19:45

0

Starting around Kotlin 1.3.31 or 1.4, this seems to be enough in build.gradle.kts:

implementation(kotlin("scripting-jsr223"))

answered Apr 06 '21 at 19:45

Simon Forsberg

13,086
10
64
108

score 0 · Answer 4 · answered May 14 '21 at 22:34

the working version nowadays is simply:

runtimeOnly("org.jetbrains.kotlin:kotlin-scripting-jsr223:${Deps.JetBrains.Kotlin.VERSION}")

which pulls in all necessary dependencies transitively.

Also the META-INF/services/javax.script.ScriptEngineFactory File seems not to be necessary if doing so.

Problems on evaluating Kotlin inside JVM with javax.script.ScriptEngineManager

4 Answers4