Sunday, February 19, 2017

... about keeping your stacktraces small

When developing an application, we often rely on logfiles to have a sense of what's going on. When an error occurs, we make sure the error is logged together with the stacktrace of the thread. The stacktrace gives us valuable information to pinpoint the problem.

At least ... that's how it used to be, before we started passing functions around and building layer upon layer. 

Below is an example of a stacktrace thrown during the handling of a request in a web container using spring mvc and rxJava:
com.mycompany.error.ValidationException: Validation failed
        at com.mycompany.upload.web.UploadValidator.checkArgument(UploadValidator.java:103)
        at com.mycompany.upload.web.UploadValidator.checkExtension(UploadValidator.java:97)
        at com.mycompany.upload.web.UploadValidator.checkCsvExtension(UploadValidator.java:89)
        at com.mycompany.upload.web.UploadValidator.validateCsvFile(UploadValidator.java:46)
        at com.mycompany.upload.web.UploadValidator.validate(UploadValidator.java:38)
        at rx.internal.util.ActionObserver.onNext(ActionObserver.java:39)
        at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:96)
        at rx.internal.util.ScalarSynchronousObservable$WeakSingleProducer.request(ScalarSynchronousObservable.java:276)
        at rx.Subscriber.setProducer(Subscriber.java:211)
        at rx.internal.operators.OnSubscribeMap$MapSubscriber.setProducer(OnSubscribeMap.java:102)
        at rx.Subscriber.setProducer(Subscriber.java:205)
        at rx.internal.util.ScalarSynchronousObservable$JustOnSubscribe.call(ScalarSynchronousObservable.java:138)
        at rx.internal.util.ScalarSynchronousObservable$JustOnSubscribe.call(ScalarSynchronousObservable.java:129)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.Observable.subscribe(Observable.java:10296)
        at rx.Observable.subscribe(Observable.java:10263)
        at rx.Observable.subscribe(Observable.java:10038)
        at com.mycompany.upload.web.UploadController.upload(UploadController.java:213)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:754)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:122)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilterInternal(BasicAuthenticationFilter.java:215)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.preauth.AbstractPreAuthenticatedProcessingFilter.doFilter(AbstractPreAuthenticatedProcessingFilter.java:121)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:96)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214)
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177)
        at org.springframework.security.web.debug.DebugFilter.invokeWithWrappedRequest(DebugFilter.java:90)
        at org.springframework.security.web.debug.DebugFilter.doFilter(DebugFilter.java:77)
        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:231)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:150)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344)
        at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:490)
        at org.apache.coyote.ajp.AjpProtocol$AjpConnectionHandler.process(AjpProtocol.java:422)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:926)
        at java.lang.Thread.run(Thread.java:745)
Caused by: rx.exceptions.OnErrorThrowable$OnNextValue: OnError while emitting onNext value: com.mycompany.upload.web.UploadContext.class
        at rx.exceptions.OnErrorThrowable.addValueAsLastCause(OnErrorThrowable.java:109)
        at rx.exceptions.Exceptions.throwOrReport(Exceptions.java:190)
        at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:98)
        ... 136 common frames omitted

It's horrific! 

Most of it doesn't tell you anything about what's going wrong. Most of it are frames from spring security, spring mvc, rxJava , container it's running on and method invocations through reflection as shown below: 
com.mycompany.error.ValidationException: Validation failed
        at com.mycompany.upload.web.UploadValidator.checkArgument(UploadValidator.java:103)
        at com.mycompany.upload.web.UploadValidator.checkExtension(UploadValidator.java:97)
        at com.mycompany.upload.web.UploadValidator.checkCsvExtension(UploadValidator.java:89)
        at com.mycompany.upload.web.UploadValidator.validateCsvFile(UploadValidator.java:46)
        at com.mycompany.upload.web.UploadValidator.validate(UploadValidator.java:38)
        at rx.internal.util.ActionObserver.onNext(ActionObserver.java:39)
        at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:96)
        at rx.internal.util.ScalarSynchronousObservable$WeakSingleProducer.request(ScalarSynchronousObservable.java:276)
        at rx.Subscriber.setProducer(Subscriber.java:211)
        at rx.internal.operators.OnSubscribeMap$MapSubscriber.setProducer(OnSubscribeMap.java:102)
        at rx.Subscriber.setProducer(Subscriber.java:205)
        at rx.internal.util.ScalarSynchronousObservable$JustOnSubscribe.call(ScalarSynchronousObservable.java:138)
        at rx.internal.util.ScalarSynchronousObservable$JustOnSubscribe.call(ScalarSynchronousObservable.java:129)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10200)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
        at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
        at rx.Observable.subscribe(Observable.java:10296)
        at rx.Observable.subscribe(Observable.java:10263)
        at rx.Observable.subscribe(Observable.java:10038)

        at com.mycompany.upload.web.UploadController.upload(UploadController.java:213)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)

        at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)

        at javax.servlet.http.HttpServlet.service(HttpServlet.java:754)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)

        at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)

        at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:122)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)

        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilterInternal(BasicAuthenticationFilter.java:215)

        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.preauth.AbstractPreAuthenticatedProcessingFilter.doFilter(AbstractPreAuthenticatedProcessingFilter.java:121)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)

        at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:96)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64)

        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)

        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214)
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177)
        at org.springframework.security.web.debug.DebugFilter.invokeWithWrappedRequest(DebugFilter.java:90)
        at org.springframework.security.web.debug.DebugFilter.doFilter(DebugFilter.java:77)

        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262)

        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)

        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:231)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:150)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344)
        at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:490)
        at org.apache.coyote.ajp.AjpProtocol$AjpConnectionHandler.process(AjpProtocol.java:422)
        at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:926)

        at java.lang.Thread.run(Thread.java:745)
Caused by: rx.exceptions.OnErrorThrowable$OnNextValue: OnError while emitting onNext value: com.mycompany.upload.web.UploadContext.class
        at rx.exceptions.OnErrorThrowable.addValueAsLastCause(OnErrorThrowable.java:109)
        at rx.exceptions.Exceptions.throwOrReport(Exceptions.java:190)
        at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:98)

        ... 136 common frames omitted
All parts marked in colour don't give me any clues about why something fails. They only obscur the real problem. 

Luckily there's a poorly documented feature in logback that allows you to filter out those frames matching a certain prefix. Here's an example of a logback configuration filtering out the frames I'm not interested in: 
<configuration scan="true">
   <contextName>myApp</contextName>

   <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <Pattern>%d{dd/MM/yyyy HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n%rootException{full
                ,rx
                ,sun.reflect
                ,java.lang.reflect
                ,org.apache.catalina
                ,org.apache.coyote
                ,org.apache.tomcat
                ,org.springframework.web.method
                ,org.springframework.web.filter
                ,org.springframework.security.web
                }</Pattern>
        </encoder>
    </appender>


    <root level="WARN">
        <appender-ref ref="CONSOLE"/>
    </root>

</configuration>
The horrific stacktrace from above is now reduced to the following:
com.mycompany.error.ValidationException: Validation failed         at com.mycompany.upload.web.UploadValidator.checkArgument(UploadValidator.java:103)         at com.mycompany.upload.web.UploadValidator.checkExtension(UploadValidator.java:97)         at com.mycompany.upload.web.UploadValidator.checkCsvExtension(UploadValidator.java:89)         at com.mycompany.upload.web.UploadValidator.validateCsvFile(UploadValidator.java:46)         at com.mycompany.upload.web.UploadValidator.validate(UploadValidator.java:38)         at com.mycompany.upload.web.UploadController.upload(UploadController.java:213)         at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)         at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)         at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)         at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)         at javax.servlet.http.HttpServlet.service(HttpServlet.java:754)         at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)         at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)         at org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:122)         at java.lang.Thread.run(Thread.java:745) Caused by: rx.exceptions.OnErrorThrowable$OnNextValue: OnError while emitting onNext value: com.mycompany.upload.web.UploadContext.class         ... 136 common frames omitted
Much easier to read, much faster to diagnose. Greetings Jan