I'd like to reset and recreate binder and form. For this purpose, I created the following method:
public void reset() {
getElement().removeAllChildren();
binder.getFields().forEach(binder::removeBinding);
createForm();
}
but it fails right now with NPE on the following line:
binder.getFields().forEach(binder::removeBinding);
java.lang.NullPointerException: null
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197) ~[na:na]
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625) ~[na:na]
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509) ~[na:na]
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499) ~[na:na]
at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150) ~[na:na]
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173) ~[na:na]
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]
at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596) ~[na:na]
at com.example.ui.forms.job.all.SearchJobForm.reset(SearchJobForm.java:205) ~[classes/:na]
at com.example.ui.views.job.all.AllJobsView.lambda$formResetButtonClickListener$dc899b5$1(AllJobsView.java:321) ~[classes/:na]
at com.vaadin.flow.component.ComponentEventBus.fireEventForListener(ComponentEventBus.java:206) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.component.ComponentEventBus.handleDomEvent(ComponentEventBus.java:448) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.component.ComponentEventBus.lambda$addDomTrigger$dd1b7957$1(ComponentEventBus.java:265) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.internal.nodefeature.ElementListenerMap.lambda$fireEvent$2(ElementListenerMap.java:447) ~[flow-server-23.1.3.jar:23.1.3]
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
at com.vaadin.flow.internal.nodefeature.ElementListenerMap.fireEvent(ElementListenerMap.java:447) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.rpc.EventRpcHandler.handleNode(EventRpcHandler.java:62) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.rpc.AbstractRpcInvocationHandler.handle(AbstractRpcInvocationHandler.java:75) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocationData(ServerRpcHandler.java:438) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.ServerRpcHandler.lambda$handleInvocations$1(ServerRpcHandler.java:419) ~[flow-server-23.1.3.jar:23.1.3]
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:419) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:320) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:115) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:40) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.VaadinService.handleRequest(VaadinService.java:1564) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.server.VaadinServlet.service(VaadinServlet.java:299) ~[flow-server-23.1.3.jar:23.1.3]
at com.vaadin.flow.spring.SpringServlet.service(SpringServlet.java:109) ~[vaadin-spring-23.1.3.jar:na]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.65.jar:4.0.FR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:711) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:459) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:353) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:313) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.springframework.web.servlet.mvc.ServletForwardingController.handleRequestInternal(ServletForwardingController.java:141) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:177) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:51) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1070) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.3.22.jar:5.3.22]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:681) ~[tomcat-embed-core-9.0.65.jar:4.0.FR]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.22.jar:5.3.22]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) ~[tomcat-embed-core-9.0.65.jar:4.0.FR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:327) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:115) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:81) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:122) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:116) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:126) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:81) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:109) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:149) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.ui.DefaultLogoutPageGeneratingFilter.doFilterInternal(DefaultLogoutPageGeneratingFilter.java:58) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:237) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:223) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:223) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:217) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.oauth2.client.web.OAuth2AuthorizationRequestRedirectFilter.doFilterInternal(OAuth2AuthorizationRequestRedirectFilter.java:178) ~[spring-security-oauth2-client-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:103) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:89) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.csrf.CsrfFilter.doFilterInternal(CsrfFilter.java:117) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:112) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:82) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:55) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:211) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:183) ~[spring-security-web-5.7.2.jar:5.7.2]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:354) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:267) ~[spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1789) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.65.jar:9.0.65]
at java.base/java.lang.Thread.run(Thread.java:833) ~[na:na]
How to properly reset the binder?
As a solution - I just create a new Binder object as it was suggested in the comment to the question