aws-sdk-java-v2: DynamoDb-enhanced NoClassDefFoundError with different ClassLoaders

It does not work well with Spring Boot Devtools too.

Dev tools uses two class loaders, one for third party libraries, and the other for project classes.

So I get something like this :

com.example.myblog.model.dynamodb.User incompatible with com.example.myblog.model.dynamodb.User java.lang.ClassCastException: com.example.myblog.model.dynamodb.User incompatible with com.example.myblog.model.dynamodb.User at com.example.myblog.repository.dynamodb.UserDynamoDbRepository.findAll(UserDynamoDbRepository.java:96) at com.example.myblog.controller.MainController.index(MainController.java:29) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:567) at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) at javax.servlet.http.HttpServlet.service(HttpServlet.java:655) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1732) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.base/java.lang.Thread.run(Thread.java:853)

I noticed that my proposed solution only works for Java 9+ but this library is 8+. Sadly I have not found any other good solution.

I have not been able to find a workaround just using the MethodHandles/Lookups provided by Java 8 alone. A workaround would be to create child ClassLoader (CL) of the bean CL in which we can load a class from which we can fetch a Lookup for that context.

However, this is rather ugly because we would need the bytecode of such class and then load it in a classloader as shown here. My proof-of-concept with bytebuddy is already convoluted enough considering this is all just a dance-around for the simple Lookup.privateLookupIn() of Java 9+.

In short:

  private static MethodHandles.Lookup getPrivateLookup(ClassLoader beanClassLoader) {
    // We use BB to be able to simply define the class below and load a copy in a child CL
    ByteBuddy bb = new ByteBuddy();
    DynamicType.Unloaded<GetLookup> clone =
        bb.rebase(GetLookup.class).name("JustRenameBecauseClassIsAlreadyLoadedInParentCL").make();
    Class<? extends Supplier<MethodHandles.Lookup>> loaded =
        clone.load(beanClassLoader).getLoaded(); // Creates child CL automatically
    try {
      Supplier<MethodHandles.Lookup> supplier = loaded.getConstructor().newInstance();
      return supplier.get();
    } catch (Exception ex) {
      throw new IllegalStateException(ex);
    }
  }

  public static class GetLookup implements Supplier<MethodHandles.Lookup> {
    public MethodHandles.Lookup get() {
      return MethodHandles.lookup();
    }
  }

Yes right, let me try, my observation was couple of months old, just now i saw another thread where you guys are discussing about fix, will try that and also update on cold start with both the approach, thanks

Quarkus extension dont solve dynamodb enhanced client issues ( native issue, dev and test issue),

To solve native issue if someone need to build native - use static dynamodb table schema

To solve dev, test issue - use %dev.quarkus.class-loading.reloadable-artifacts=software.amazon.awssdk:dynamodb-enhanced

%test.quarkus.class-loading.reloadable-artifacts=software.amazon.awssdk:dynamodb-enhanced

edit Quarkus dynamodb extension is needed and on top of that we have to follow above mentioned steps to make dynamodb enhanced client work( just dynamodb client will work with just extension but to make enhanced client work we need to make some extra changes than just adding quarkus dynamodb extension)

Same issue here with 2.11.1, even setting quarkus.class-loading.reloadable-artifact

Sadly have been stuck on this and have to avoid enhanced dynamodb up to now in our native images. When this issue gets resolved it would simplify our business code a lot