Need help with Kotlin syntax to make a call to a Java method defined with generics


This is the Java method signature I am trying to call from Kotlin:

<T> T source(String aURI, Class<T> aRepresentationClass) throws NKFException;

In Java I can do this:

IHDSNode node = context.source(“res:/myResource”, IHDSNode.class);

I tried this in Kotlin:

  val node  = context.source("active:something",IHDSNode.class )

but I get an error message:

“Expression 'class ) ’ cannot be a selector  (occur after a dot)”

which references the “.class” part of the method call.

What syntax do I need to construct this method call?

Thank you! – Randy


To get class use this

val clz: Class<String> = javaClass<String>()


This is helpful. Thank you.

I’m still stuck, and maybe this is a bug, an IDE issue, or still something I do not understand.

When I create the following in IntelliJ (latest 12 release and latest Kotlin plugin (m3.1) the text “javaClass” is in red and the fly-over error message says “Unresolved reference: javaClass”. Sounds like I’m missing an import, but this is supposed to be a “core” feature of Kotlin.

Here’s my code copied from IntelliJ:

package net.databliss.netkernel.layer0.endpoints import org.netkernel.module.standard.endpoint.StandardAccessorImpl import org.netkernel.layer0.nkf.INKFRequestContext import org.netkernel.layer0.representation.IHDSNode class TestEndpoint : StandardAccessorImpl()   {   {   declareThreadSafe()   }   override public fun onSource(context: INKFRequestContext) {      val request = context.createRequest("res:/resources/tests/testlist.xml")   request?.setRepresentationClass(javaClass<IHDSNode>())   val node : IHDSNode  = context.issueRequest(request) as IHDSNode   val aNode = node.getFirstNode("//information")   context.createResponseFrom(aNode)   } }


Does the compilation fail if you hit Ctrl+F9 (Cmd+F9 on Mac)?


Yes. It fails.

Information:Using kotlinHome=/Users/randolph.kahle/Library/Application Support/IntelliJIdea12/Kotlin/kotlinc Information:Invoking in-process compiler org.jetbrains.jet.cli.jvm.K2JVMCompiler with arguments [-module, /Users/randolph.kahle/development/source/netkernel/package/bb-overlay/out/production/, -output, /Users/randolph.kahle/development/source/netkernel/package/bb-overlay/out/production/, -tags, -verbose, -version, -noStdlib, -noJdkAnnotations, -noJdk] Information:Kotlin Compiler version 0.4.68 Information:Compilation completed with 1 error and 1 warning in 1 sec Information:1 error Information:1 warning /Users/randolph.kahle/development/source/netkernel/module/   Warning:Warning:line (14)The corresponding parameter in the supertype 'StandardAccessorImpl' is named 'aContext'. This may cause problems when calling this function with named arguments.   Error:Error:line (18)Unresolved reference: javaClass


Does this code work for you?


import java.util.concurrent.*

fun main(args: Array<String>) {


I hope putting it into a package does not conflict...

This code:

package net.databliss.kotlin

import java.util.concurrent.*

fun main(args: Array<String>) {

Has “println” and “javaClass” highlighted in red and says it cannot resolve.



My guess is you have no Kotlin library set up for your project. This should be taken care of by a notification bar sliding from the top of your editor. Did you see one?



Thank you for following up on this.

Your comment makes sense to me. I do not see any slider.

I removed the Kotlin plugin and then re-downloaded it. Same result.

What is strange is that the compiler and plugin were working fine and then I updated both Leda and (I believe) the plugin for M3.1 and then it stopped working.

I’m on OS X Mountain Lion - latest version…

Do you think I should remove Leda and the plugin and and try to start fresh?

Thank you – Randy



I did remove Leda and the plug in. I cleared all cache areas, etc. in OS X. I downloaded the latest Leda and then installed the Kotlin plugin.

Unfortunately, the results are the same.




Could you archive your project and post it here or send it to me at andrey.breslav at Thanks



I sent it via email earlier this morning. Please let me know if you do not receive it.


Replied by email with some instructions. Long story short: you didn't configure your dependencies in pom.xml, and the IDE got confused. Maven set-up instructions: In your case it suffices to delete pom.xml