Hi everyone,
We’re experiencing an intermittent NullPointerException when reloading certain views (F5) in our application. It happens in views that contain a Grid component, specifically in our Chat, Inbox, Records and Missed Calls views. When it occurs, users are forced to log out and back in to recover.
Environment:
- Jmix version: 2.7.4
- Vaadin version: 24.9.9
- Java version: 21.0.4
- Deployment: Tomcat / Spring Boot
Error message:
java.lang.NullPointerException: Cannot invoke
"com.vaadin.flow.server.VaadinSession.checkHasLock()"
because "this.this$0.session" is null
Full stack trace:
Click to expand
``` java.lang.NullPointerException: Cannot invoke "com.vaadin.flow.server.VaadinSession.checkHasLock()" because "this.this$0.session" is null at com.vaadin.flow.component.internal.UIInternals$PendingJavaScriptInvocationDetachListener.removePendingInvocation(UIInternals.java:687) at com.vaadin.flow.component.internal.UIInternals$PendingJavaScriptInvocationDetachListener.onInvocationCompleted(UIInternals.java:697) at com.vaadin.flow.component.internal.UIInternals.lambda$registerDetachListenerForPendingInvocation$b12ef46$1(UIInternals.java:665) at com.vaadin.flow.component.internal.PendingJavaScriptInvocation.cancelExecution(PendingJavaScriptInvocation.java:126) at com.vaadin.flow.component.grid.Grid.updateClientSideSorterIndicators(Grid.java:4168) at com.vaadin.flow.component.grid.Grid.onAttach(Grid.java:4088) at com.vaadin.flow.component.ComponentUtil.onComponentAttach(ComponentUtil.java:290) at com.vaadin.flow.internal.nodefeature.ComponentMapping.lambda$onAttach$0(ComponentMapping.java:104) at java.base/java.util.Optional.ifPresent(Optional.java:178) at com.vaadin.flow.internal.nodefeature.ComponentMapping.onAttach(ComponentMapping.java:103) at com.vaadin.flow.internal.StateNode.lambda$fireAttachListeners$9(StateNode.java:934) at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:184) at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179) at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:1024) at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509) at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499) at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151) at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174) at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596) at com.vaadin.flow.internal.StateNode.forEachFeature(StateNode.java:377) at com.vaadin.flow.internal.StateNode.fireAttachListeners(StateNode.java:934) at com.vaadin.flow.internal.StateNode.onAttach(StateNode.java:335) at com.vaadin.flow.internal.StateNode.setParent(StateNode.java:287) at com.vaadin.flow.internal.nodefeature.NodeFeature.attachPotentialChild(NodeFeature.java:80) at com.vaadin.flow.internal.nodefeature.StateNodeNodeList.add(StateNodeNodeList.java:55) at com.vaadin.flow.internal.nodefeature.ElementChildrenList.add(ElementChildrenList.java:44) at com.vaadin.flow.dom.impl.AbstractNodeStateProvider.insertChild(AbstractNodeStateProvider.java:107) at com.vaadin.flow.dom.Node.insertChild(Node.java:391) at com.vaadin.flow.dom.Node.appendChild(Node.java:163) at com.vaadin.flow.dom.Node.appendChild(Node.java:147) at com.vaadin.flow.component.internal.UIInternalUpdater.updateRoot(UIInternalUpdater.java:71) at io.jmix.tabbedmode.JmixUI.setTopLevelView(JmixUI.java:764) at io.jmix.tabbedmode.JmixUI.movePreservedViewCache(JmixUI.java:601) at io.jmix.tabbedmode.JmixUI.handlePageLoad(JmixUI.java:578) at io.jmix.tabbedmode.JmixUI.handleNavigation(JmixUI.java:555) at io.jmix.tabbedmode.JmixUI.lambda$handlePageLoad$0(JmixUI.java:584) at io.jmix.tabbedmode.JmixUI.lambda$obtainJmixUiId$46dec084$1(JmixUI.java:678) at com.vaadin.flow.component.page.PendingJavaScriptResult.lambda$then$3fde283c$1(PendingJavaScriptResult.java:113) at com.vaadin.flow.component.internal.PendingJavaScriptInvocation.complete(PendingJavaScriptInvocation.java:96) at com.vaadin.flow.server.communication.UidlWriter.lambda$createReturnValueChannel$d9004ac5$1(UidlWriter.java:330) at com.vaadin.flow.internal.nodefeature.ReturnChannelMap.lambda$registerChannel$2a20409b$1(ReturnChannelMap.java:124) at com.vaadin.flow.internal.nodefeature.ReturnChannelMap$ChannelImpl.invoke(ReturnChannelMap.java:74) at com.vaadin.flow.server.communication.ReturnChannelHandler.handleNode(ReturnChannelHandler.java:78) at com.vaadin.flow.server.communication.rpc.AbstractRpcInvocationHandler.handle(AbstractRpcInvocationHandler.java:79) at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocationData(ServerRpcHandler.java:568) at com.vaadin.flow.server.communication.ServerRpcHandler.lambda$handleInvocations$6(ServerRpcHandler.java:549) at java.base/java.util.ArrayList.forEach(ArrayList.java:1596) at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:549) at com.vaadin.flow.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:376) at com.vaadin.flow.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:136) at com.vaadin.flow.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:63) at com.vaadin.flow.server.VaadinService.handleRequest(VaadinService.java:1879) at com.vaadin.flow.server.VaadinServlet.service(VaadinServlet.java:398) at com.vaadin.flow.spring.SpringServlet.service(SpringServlet.java:106) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:610) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:392) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:321) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:266) at org.springframework.web.servlet.mvc.ServletForwardingController.handleRequestInternal(ServletForwardingController.java:142) at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:178) at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:51) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:979) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:547) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:614) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at io.jmix.core.impl.logging.LogMdcFilter.doFilterInternal(LogMdcFilter.java:28) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:108) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:108) at org.springframework.security.web.FilterChainProxy.lambda$doFilterInternal$3(FilterChainProxy.java:231) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:365) at org.springframework.security.web.access.intercept.AuthorizationFilter.doFilter(AuthorizationFilter.java:101) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:125) at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:131) at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:85) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:100) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:114) at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:105) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:179) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:151) at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:129) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:235) at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:229) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:107) at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:93) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.csrf.CsrfFilter.doFilterInternal(CsrfFilter.java:117) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:82) at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:69) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:62) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:233) at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:191) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) at org.springframework.web.filter.ServletRequestPathFilter.doFilter(ServletRequestPathFilter.java:52) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:74) at org.springframework.security.config.annotation.web.configuration.WebSecurityConfiguration$CompositeFilterChainProxy.doFilter(WebSecurityConfiguration.java:319) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) at org.springframework.web.servlet.handler.HandlerMappingIntrospector.lambda$createCacheFilter$4(HandlerMappingIntrospector.java:267) at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:74) at org.springframework.security.config.annotation.web.configuration.WebMvcSecurityConfiguration$CompositeFilterChainProxy.doFilter(WebMvcSecurityConfiguration.java:240) at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:362) at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:278) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:162) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:138) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:165) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:88) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:482) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:113) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:83) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:72) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:903) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1774) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) at java.base/java.lang.VirtualThread.run(VirtualThread.java:329) ```What’s happening:
Looking at the stack trace, the call chain is:
Grid.updateClientSideSorterIndicators(Grid.java:4168)
→ Grid.onAttach(Grid.java:4088)
→ JmixUI.movePreservedViewCache(JmixUI.java:601)
→ JmixUI.handlePageLoad(JmixUI.java:578)
On page reload, JmixUI.movePreservedViewCache attempts to restore a cached view containing a Grid. During the re-attach process, Vaadin tries to cancel a pending JavaScript invocation from the previous lifecycle (updateClientSideSorterIndicators → cancelExecution → PendingJavaScriptInvocationDetachListener). At that point, session is null — it hasn’t been assigned to the new context yet, or has already been cleared from the previous one.
Reproduction:
- The issue is intermittent in production (multiple concurrent users) in several views but consistently reproducible in our development environment by simply pressing F5 in one specific view.
- It does not seem related to any custom business logic — the stack trace points entirely to Jmix/Vaadin internals.
Has anyone else encountered this? Is there a known fix or recommended approach for this scenario?
Thank you in advance.