IllegalArgumentException thrown when using Kotlin unsigned integer value class as annotated method parameter

[evo13th]

Summary

IllegalArgumentException is thrown when Kotlin unsigned value class (ULong, UInt) is used as the request parameter. However it's working as expected when the value class is signed (Long, Int)

Environment

• Spring Framework version 6.2.2
• JVM version 21
• Kotlin version 2.1.10

Minimal Example Code

import org.springframework.web.bind.annotation.GetMapping
import org.springframework.web.bind.annotation.RequestParam
import org.springframework.web.bind.annotation.RestController

@RestController
class IntegerController {
    @GetMapping("/unsigned")
    suspend fun doUnsigned(@RequestParam param: UnsignedIntegerValueClass): String {
        // got exception
        return param.value.toString()
    }

    @GetMapping("/unsigned-path/{param}")
    suspend fun doUnsigned2(@PathVariable param: UnsignedIntegerValueClass): String {
        // got exception too
        return param.value.toString()
    }

    @GetMapping("/signed")
    suspend fun doSigned(@RequestParam param: SignedIntegerValueClass): String {
        // works
        return param.value.toString()
    }

    @GetMapping("/signed-path/{param}")
    suspend fun doSigned2(@PathVariable param: SignedIntegerValueClass): String {
        // also works
        return param.value.toString()
    }

    @JvmInline
    value class UnsignedIntegerValueClass(val value: ULong)

    @JvmInline
    value class SignedIntegerValueClass(val value: Long)
}

Stacktrace

java.lang.IllegalArgumentException: object is not an instance of declaring class
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.checkReceiver(DirectMethodHandleAccessor.java:197) ~[na:na]
	Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Assembly trace from producer [reactor.core.publisher.MonoCreate] :
	reactor.core.publisher.Mono.create(Mono.java:203)
	kotlinx.coroutines.reactor.MonoKt.monoInternal(Mono.kt:83)
Error has been observed at the following site(s):
	*_______________________Mono.create ⇢ at kotlinx.coroutines.reactor.MonoKt.monoInternal(Mono.kt:83)
	|_                      Mono.filter ⇢ at org.springframework.core.CoroutinesUtils.invokeSuspendingFunction(CoroutinesUtils.java:148)
	|_                  Mono.onErrorMap ⇢ at org.springframework.core.CoroutinesUtils.invokeSuspendingFunction(CoroutinesUtils.java:149)
	|_                      Mono.handle ⇢ at org.springframework.web.reactive.result.method.InvocableHandlerMethod$KotlinDelegate.invokeFunction(InvocableHandlerMethod.java:335)
	|_                         Mono.map ⇢ at org.springframework.http.codec.json.AbstractJackson2Encoder.lambda$encode$7(AbstractJackson2Encoder.java:159)
	|_                        Mono.flux ⇢ at org.springframework.http.codec.json.AbstractJackson2Encoder.lambda$encode$7(AbstractJackson2Encoder.java:160)
	*__MonoCreate$DefaultMonoSink.error ⇢ at kotlinx.coroutines.reactor.MonoCoroutine.onCancelled(Mono.kt:109)
	*______________Flux.deferContextual ⇢ at org.springframework.http.codec.json.AbstractJackson2Encoder.encode(AbstractJackson2Encoder.java:152)
	|_               Flux.singleOrEmpty ⇢ at org.springframework.http.codec.EncoderHttpMessageWriter.write(EncoderHttpMessageWriter.java:128)
	|_               Mono.switchIfEmpty ⇢ at org.springframework.http.codec.EncoderHttpMessageWriter.write(EncoderHttpMessageWriter.java:129)
	|_                     Mono.flatMap ⇢ at org.springframework.http.codec.EncoderHttpMessageWriter.write(EncoderHttpMessageWriter.java:134)
	|_                 Mono.doOnDiscard ⇢ at org.springframework.http.codec.EncoderHttpMessageWriter.write(EncoderHttpMessageWriter.java:140)
	|_                       checkpoint ⇢ Handler com.example.demo.controller.IntegerController#doUnsigned-aKQQcxY(long, Continuation) [DispatcherHandler]
	|_               Mono.onErrorResume ⇢ at org.springframework.web.reactive.DispatcherHandler.lambda$handleResultMono$7(DispatcherHandler.java:176)
	*______________________Mono.flatMap ⇢ at org.springframework.web.reactive.DispatcherHandler.lambda$handleResultMono$6(DispatcherHandler.java:177)
	*______________________Mono.flatMap ⇢ at org.springframework.web.reactive.DispatcherHandler.handleResultMono(DispatcherHandler.java:172)
	*______________________Mono.flatMap ⇢ at org.springframework.web.reactive.DispatcherHandler.handle(DispatcherHandler.java:154)
	*________________________Mono.defer ⇢ at org.springframework.web.server.handler.DefaultWebFilterChain.filter(DefaultWebFilterChain.java:106)
	|_                   Mono.doOnError ⇢ at org.springframework.web.server.handler.ExceptionHandlingWebHandler.handle(ExceptionHandlingWebHandler.java:84)
	|_               Mono.onErrorResume ⇢ at org.springframework.web.server.handler.ExceptionHandlingWebHandler.handle(ExceptionHandlingWebHandler.java:85)
	|_                   Mono.doOnError ⇢ at org.springframework.web.server.handler.ExceptionHandlingWebHandler.handle(ExceptionHandlingWebHandler.java:84)
	*________________________Mono.error ⇢ at org.springframework.web.server.handler.ExceptionHandlingWebHandler$CheckpointInsertingHandler.handle(ExceptionHandlingWebHandler.java:106)
	|_                       checkpoint ⇢ HTTP GET "/unsigned?param=100" [ExceptionHandlingWebHandler]
Original Stack Trace:
		at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.checkReceiver(DirectMethodHandleAccessor.java:197) ~[na:na]
		at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:99) ~[na:na]
		at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na]
		at kotlin.reflect.jvm.internal.calls.ValueClassAwareCaller.call(ValueClassAwareCaller.kt:200) ~[kotlin-reflect-2.1.10.jar:2.1.10-release-473]
		at kotlin.reflect.jvm.internal.KCallableImpl.call(KCallableImpl.kt:108) ~[kotlin-reflect-2.1.10.jar:2.1.10-release-473]
		at org.springframework.core.CoroutinesUtils.lambda$invokeSuspendingFunction$3(CoroutinesUtils.java:138) ~[spring-core-6.2.2.jar:6.2.2]
		at kotlin.coroutines.intrinsics.IntrinsicsKt__IntrinsicsJvmKt$createCoroutineUnintercepted$$inlined$createCoroutineFromSuspendFunction$IntrinsicsKt__IntrinsicsJvmKt$4.invokeSuspend(IntrinsicsJvm.kt:241) ~[kotlin-stdlib-2.1.10.jar:2.1.10-release-473]
		at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith$$$capture(ContinuationImpl.kt:33) ~[kotlin-stdlib-2.1.10.jar:2.1.10-release-473]
		at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt) ~[kotlin-stdlib-2.1.10.jar:2.1.10-release-473]
		at kotlinx.coroutines.internal.DispatchedContinuationKt.resumeCancellableWith(DispatchedContinuation.kt:363) ~[kotlinx-coroutines-core-jvm-1.8.1.jar:na]
		at kotlinx.coroutines.intrinsics.CancellableKt.startCoroutineCancellable(Cancellable.kt:26) ~[kotlinx-coroutines-core-jvm-1.8.1.jar:na]
		at kotlinx.coroutines.intrinsics.CancellableKt.startCoroutineCancellable$default(Cancellable.kt:21) ~[kotlinx-coroutines-core-jvm-1.8.1.jar:na]
		at kotlinx.coroutines.CoroutineStart.invoke(CoroutineStart.kt:88) ~[kotlinx-coroutines-core-jvm-1.8.1.jar:na]
		at kotlinx.coroutines.AbstractCoroutine.start(AbstractCoroutine.kt:123) ~[kotlinx-coroutines-core-jvm-1.8.1.jar:na]
		at kotlinx.coroutines.reactor.MonoKt.monoInternal$lambda$2(Mono.kt:88) ~[kotlinx-coroutines-reactor-1.8.1.jar:na]
		at reactor.core.publisher.MonoCreate.subscribe(MonoCreate.java:61) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalFluxOperator.subscribe(InternalFluxOperator.java:68) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxDeferContextual.subscribe(FluxDeferContextual.java:57) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:165) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxPeekFuseable$PeekFuseableSubscriber.onNext(FluxPeekFuseable.java:210) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.complete(MonoIgnoreThen.java:294) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.onNext(MonoIgnoreThen.java:188) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:158) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip$ZipCoordinator.signal(MonoZip.java:297) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip$ZipInner.onNext(MonoZip.java:478) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators$ScalarSubscription.request(Operators.java:2571) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.request(MonoPeekTerminal.java:139) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip$ZipInner.onSubscribe(MonoZip.java:470) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onSubscribe(MonoPeekTerminal.java:152) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoJust.subscribe(MonoJust.java:55) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip$ZipCoordinator.request(MonoZip.java:220) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.request(MonoFlatMap.java:194) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.onSubscribe(MonoIgnoreThen.java:135) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onSubscribe(MonoFlatMap.java:117) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip.subscribe(MonoZip.java:129) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:53) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:241) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.onComplete(MonoIgnoreThen.java:204) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onComplete(MonoFlatMap.java:189) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators.complete(Operators.java:137) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoZip.subscribe(MonoZip.java:121) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Mono.subscribe(Mono.java:4576) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:265) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:165) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:74) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxConcatMapNoPrefetch$FluxConcatMapNoPrefetchSubscriber.innerNext(FluxConcatMapNoPrefetch.java:259) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:865) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.onNext(FluxMapFuseable.java:129) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators$ScalarSubscription.request(Operators.java:2571) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.request(MonoPeekTerminal.java:139) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxMapFuseable$MapFuseableSubscriber.request(FluxMapFuseable.java:171) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.request(Operators.java:2331) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxConcatMapNoPrefetch$FluxConcatMapNoPrefetchSubscriber.request(FluxConcatMapNoPrefetch.java:339) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoNext$NextSubscriber.request(MonoNext.java:108) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.set(Operators.java:2367) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Operators$MultiSubscriptionSubscriber.onSubscribe(Operators.java:2241) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoNext$NextSubscriber.onSubscribe(MonoNext.java:70) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxConcatMapNoPrefetch$FluxConcatMapNoPrefetchSubscriber.onSubscribe(FluxConcatMapNoPrefetch.java:164) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:201) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:83) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:53) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Mono.subscribe(Mono.java:4576) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:265) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.Mono.subscribe(Mono.java:4576) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:265) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.MonoDeferContextual.subscribe(MonoDeferContextual.java:55) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:76) ~[reactor-core-3.7.2.jar:3.7.2]
		at reactor.netty.http.server.HttpServer$HttpServerHandle.onStateChange(HttpServer.java:1211) ~[reactor-netty-http-1.2.2.jar:1.2.2]
		at reactor.netty.ReactorNetty$CompositeConnectionObserver.onStateChange(ReactorNetty.java:716) ~[reactor-netty-core-1.2.2.jar:1.2.2]
		at reactor.netty.transport.ServerTransport$ChildObserver.onStateChange(ServerTransport.java:486) ~[reactor-netty-core-1.2.2.jar:1.2.2]
		at reactor.netty.http.server.HttpServerOperations.handleDefaultHttpRequest(HttpServerOperations.java:850) ~[reactor-netty-http-1.2.2.jar:1.2.2]
		at reactor.netty.http.server.HttpServerOperations.onInboundNext(HttpServerOperations.java:776) ~[reactor-netty-http-1.2.2.jar:1.2.2]
		at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:115) ~[reactor-netty-core-1.2.2.jar:1.2.2]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:267) ~[reactor-netty-http-1.2.2.jar:1.2.2]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:442) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:346) ~[netty-codec-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:318) ~[netty-codec-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:442) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1357) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:440) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:868) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:788) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562) ~[netty-transport-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.117.Final.jar:4.1.117.Final]
		at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) ~[netty-common-4.1.117.Final.jar:4.1.117.Final]
		at java.base/java.lang.Thread.run(Thread.java:1583) ~[na:na]

From my short investigation, it might have something to do with the Kotlin convert the unsigned to signed in the bytecode and comparing that signed class against the Kotlin unsigned class.

[sdeleuze]

I can reproduce, it is due to the fact that, unlike with signed variant, unsigned inline value classes require a kotlin.UInt parameter, not a kotlin.Int one that can be created from the input Integer. I have requested Kotlin team guidance.

[sdeleuze]

So unsigned types and inline classes themselves, that means we can support them by doing the boxing/unboxing thing recursively.