# NoClassDefFoundError OkHttpCloudEventsIntrospectionWrapper **URL:** \ **Category:** Open Q&A\ **Tags:** oneagent\ **Created:** [November 19, 2024, 10:27pm UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971 "2024-11-19T22:27:13Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![achang](https://avatars.discourse-cdn.com/v4/letter/a/5e9695/32.png) [@achang](https://community.dynatrace.com/u/achang)\ **Post date:** [November 19, 2024, 10:27pm UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/1 "2024-11-19T22:27:13Z")
I have One Agent (1.299.50.20240930-123825) running in my Spring Boot application. However, I am receiving the error below: java.lang.NoClassDefFoundError: Could not initialize class com.dynatrace.agent.introspection.cloudevents.outgoing.okhttp.OkHttpCloudEventsIntrospectionWrapper I am making use of: OpenFeign - 11 okhttp3 - 4.9.3 ---
**Author:** ![Peter\_Youssef](https://dub1.discourse-cdn.com/dynatrace/user_avatar/community.dynatrace.com/peter_youssef/32/14668_2.png) [@Peter\_Youssef](https://community.dynatrace.com/u/Peter_Youssef)\ **Post date:** [November 20, 2024, 5:35am UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/2 "2024-11-20T05:35:39Z")
Hello [@achang](https://community.dynatrace.com/user/83339) can you please check if the technology is supported, as long as you have an updated version of OneAgent deployed: - [OneAgent platform and capability support matrix — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/technology-support/oneagent-platform-and-capability-support-matrix) - [Technology support — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/technology-support) BR, Peter ---
**Author:** ![Peter\_Youssef](https://dub1.discourse-cdn.com/dynatrace/user_avatar/community.dynatrace.com/peter_youssef/32/14668_2.png) [@Peter\_Youssef](https://community.dynatrace.com/u/Peter_Youssef)\ **Post date:** [November 20, 2024, 5:38am UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/3 "2024-11-20T05:38:03Z")
Hi [@achang](https://community.dynatrace.com/user/83339) - Would you mind sharing the related logs for further investigation. - Another solution is to update the application related technologies, uninstall OA, remove all directories and then re-install it again “fresh deployment”. Hoping it adds value Regards, Peter ---
**Author:** ![achang](https://avatars.discourse-cdn.com/v4/letter/a/5e9695/32.png) [@achang](https://community.dynatrace.com/u/achang)\ **Post date:** [November 20, 2024, 10:32am UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/4 "2024-11-20T10:32:19Z")
Hi [@Peter\_Youssef](https://community.dynatrace.com/user/51369), Thanks for the ideas. Please find the stack trace below: ```markup org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class com.dynatrace.agent.introspection.cloudevents.outgoing.okhttp.OkHttpCloudEventsIntrospectionWrapper at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1086) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:964) 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:670) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) at javax.servlet.http.HttpServlet.service(HttpServlet.java:779) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:102) 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.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:102) 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.ForwardedHeaderFilter.doFilterInternal(ForwardedHeaderFilter.java:156) 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.ApplicationDispatcher.invoke(ApplicationDispatcher.java:711) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:461) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:385) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:313) at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:403) at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:249) at org.apache.catalina.core.StandardHostValve.throwable(StandardHostValve.java:344) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) 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:360) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:893) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1789) 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.lang.Thread.run(Thread.java:750) Caused by: java.lang.NoClassDefFoundError: Could not initialize class com.dynatrace.agent.introspection.cloudevents.outgoing.okhttp.OkHttpCloudEventsIntrospectionWrapper at okhttp3.internal.connection.RealCall.execute(RealCall.kt) at feign.okhttp.OkHttpClient.execute(OkHttpClient.java:169) at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:119) at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:89) at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:100) at com.sun.proxy.$Proxy113.getRemoteConfig(Unknown Source) at com.example.repository.remoteconfig.RemoteConfigRepository.fetchRemoteConfig(RemoteConfigRepository.kt:20) at com.example.repository.remoteconfig.RemoteConfigRepository$$FastClassBySpringCGLIB$$b28d96de.invoke() at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at org.springframework.cache.interceptor.CacheInterceptor.lambda$invoke$0(CacheInterceptor.java:54) at org.springframework.cache.interceptor.CacheAspectSupport.invokeOperation(CacheAspectSupport.java:366) at org.springframework.cache.interceptor.CacheAspectSupport.execute(CacheAspectSupport.java:421) at org.springframework.cache.interceptor.CacheAspectSupport.execute(CacheAspectSupport.java:345) at org.springframework.cache.interceptor.CacheInterceptor.invoke(CacheInterceptor.java:64) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) at com.example.repository.remoteconfig.RemoteConfigRepository$$EnhancerBySpringCGLIB$$26736658.fetchRemoteConfig() at com.example.service.remoteconfig.RemoteConfigService.getMappedCountryParameters(RemoteConfigService.kt:88) at com.example.service.remoteconfig.RemoteConfigService.getProgram(RemoteConfigService.kt:46) at com.example.server.interceptors.authentication.AuthenticationHandlerInterceptor.extractClientCredentials(AuthenticationHandlerInterceptor.kt:84) at com.example.server.interceptors.authentication.AuthenticationHandlerInterceptor.preHandle(AuthenticationHandlerInterceptor.kt:43) at org.springframework.web.servlet.HandlerExecutionChain.applyPreHandle(HandlerExecutionChain.java:148) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1066) ... 38 common frames omitted ``` Looking at [Technology support — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/technology-support) I’m not seeing support for Feign under Web Services. We do make use of Spring in our application so I am going to try and make use of Spring Web Services to facilitate the API calls to see if that sorts out the issue. I don’t think reinstalling One Agent will help. The application is running within AWS ECS and when it starts up another container is created that does a fresh install of One Agent and so it has been reinstalled a few times to no avail. ---
**Author:** ![Peter\_Youssef](https://dub1.discourse-cdn.com/dynatrace/user_avatar/community.dynatrace.com/peter_youssef/32/14668_2.png) [@Peter\_Youssef](https://community.dynatrace.com/u/Peter_Youssef)\ **Post date:** [November 20, 2024, 5:14pm UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/5 "2024-11-20T17:14:21Z")
Hello [@achang](https://community.dynatrace.com/user/83339) Appreciate your trust and inputs. **First of all:** - Make sure that DT doc procedures have been applied properly if it was the followed deployment method : [Monitor Amazon ECS on EC2 — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/amazon-web-services/integrate-into-aws/aws-ecs) - If there is another method you have followed kindly share it for further validation. - Another configurations to validate “proxy configurations”: [Proxy for ActiveGate — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/dynatrace-activegate/configuration/set-up-proxy-authentication-for-activegate) - Can you check if the highlighted technology versions are updated or not as per the current situation. **Dev team can also validate a similar case on**  :stack\_overflow:: - [https://stackoverflow.com/questions/71335893/java-lang-noclassdeffounderror-could-not-initialize-class-okhttp3-okhttpclient](https://stackoverflow.com/questions/71335893/java-lang-noclassdeffounderror-could-not-initialize-class-okhttp3-okhttpclient) Keep us posted. BR,  peter ---
**Author:** ![Peter\_Youssef](https://dub1.discourse-cdn.com/dynatrace/user_avatar/community.dynatrace.com/peter_youssef/32/14668_2.png) [@Peter\_Youssef](https://community.dynatrace.com/u/Peter_Youssef)\ **Post date:** [November 20, 2024, 5:22pm UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/6 "2024-11-20T17:22:04Z")
Hi [@achang](https://community.dynatrace.com/user/83339) 👨‍💻 I’d appreciate checking with the deployment team which integration method has been followed: - This 🙂 [Deploy OneAgent using AWS Systems Manager Distributor — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/amazon-web-services/integrate-into-aws/aws-ec2/deploy-oneagent-using-aws-systems-manager-distributor) - Or This 🤔  [Monitor Amazon Web Services with CloudWatch metrics — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/amazon-web-services/integrate-with-aws/cloudwatch-metrics) - TYT in validation and keep us posted for further resolution progress. BR, Peter ---
**Author:** ![achang](https://avatars.discourse-cdn.com/v4/letter/a/5e9695/32.png) [@achang](https://community.dynatrace.com/u/achang)\ **Post date:** [November 20, 2024, 9:43pm UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/7 "2024-11-20T21:43:42Z")
Hi [@Peter\_Youssef](https://community.dynatrace.com/user/51369) , The approach that we took to make use of One Agent was: [Monitor AWS Fargate — Dynatrace Docs](https://docs.dynatrace.com/docs/ingest-from/amazon-web-services/integrate-into-aws/aws-fargate#runtime). I managed to solve the issue. It appears that Feign isn’t supported so I switched to OpenFeign (I incorrectly listed this as something we were using above) which is. Once again, thank you for the direction that you provided on this matter. ---
**Author:** ![Peter\_Youssef](https://dub1.discourse-cdn.com/dynatrace/user_avatar/community.dynatrace.com/peter_youssef/32/14668_2.png) [@Peter\_Youssef](https://community.dynatrace.com/u/Peter_Youssef)\ **Post date:** [November 21, 2024, 10:26am UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/8 "2024-11-21T10:26:21Z")
Hi [@achang](https://community.dynatrace.com/user/83339) 👨‍💻 Glad to hear you managed to resolve the highlighted issue 😊, Best wishes. KR, Peter ---
**Author:** ![achang](https://avatars.discourse-cdn.com/v4/letter/a/5e9695/32.png) [@achang](https://community.dynatrace.com/u/achang)\ **Post date:** [December 10, 2024, 11:16am UTC](https://community.dynatrace.com/t/noclassdeffounderror-okhttpcloudeventsintrospectionwrapper/48971/9 "2024-12-10T11:16:08Z")
The move to OpenFeign didn’t resolve the issue. When the API was started up we made use of the flag -javaagent:aws-opentelemetry-agent.jar because we were using OpenTelemetry in the past. We no longer use OpenTelemetry and removing the flag resolved the issue for us.