I have been seeing this a bit recently (I'm using KeyCloak 1.2.0). I haven't tracked down a reproducible test case yet, but I'm wondering if there are situations where Tomcat will attempt to stop the value before it is started, which leads to nodesRegistrationManagement being null.

Maybe it is worth adding a null check in AbstractKeycloakAuthenticatorValve.beforeStop()?

java.lang.NullPointerException
     at org.keycloak.adapters.tomcat.AbstractKeycloakAuthenticatorValve.beforeStop(AbstractKeycloakAuthenticatorValve.java:130)
     at org.keycloak.adapters.tomcat.AbstractKeycloakAuthenticatorValve.lifecycleEvent(AbstractKeycloakAuthenticatorValve.java:67)
     at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
     at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
     at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:226)
     at org.apache.catalina.util.LifecycleBase.destroy(LifecycleBase.java:272)
     at org.apache.catalina.core.ContainerBase.removeChild(ContainerBase.java:1041)
     at org.apache.catalina.startup.HostConfig.deleteRedeployResources(HostConfig.java:1300)
     at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java:1251)
     at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1460)
     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:483)
     at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:301)
     at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
     at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
     at org.apache.catalina.manager.ManagerServlet.check(ManagerServlet.java:1445)
     at org.apache.catalina.manager.ManagerServlet.undeploy(ManagerServlet.java:1381)
     at org.apache.catalina.manager.HTMLManagerServlet.undeploy(HTMLManagerServlet.java:674)
     at org.apache.catalina.manager.HTMLManagerServlet.doPost(HTMLManagerServlet.java:215)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
     at org.apache.catalina.filters.CsrfPreventionFilter.doFilter(CsrfPreventionFilter.java:213)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
     at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
     at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:581)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
     at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
     at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
     at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
     at java.lang.Thread.run(Thread.java:745)

--
Matthew Casperson
Senior Front End Developer
Technology, Space & Distribution
Auto & General Holdings Pty Ltd
P: 07) 3377 8751 (Direct: 3377 8751)
F: 07) 3377 8833



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