Identifying cause of NPE in Struts ExceptionInterceptor

[Burton Rhodes <bu...@gmail.com>]

I am having trouble identifying where a NPE is being generated.  I have the
exception stacktrace below with a non-descriptive line at the end.  Am I
missing a vital line in the stacktrace or does anyone have an idea how I
can log more information on this?

[My ExceptionInterceptor.java]

public class ExceptionInterceptor extends ExceptionMappingInterceptor {

    @Override
    public String intercept(ActionInvocation invocation) throws Exception {

        String result;

        try {
            result = invocation.invoke();

        } catch (Exception e) {

            // Log exception
            if (isLogEnabled()) {
                String userName =
SecurityContextHolder.getContext().getAuthentication().getName();
                Exception ex = new Exception("Uncaught error by user:"
+ userName, e);
                handleLogging(ex);
            }

            List<ExceptionMappingConfig> exceptionMappings =
invocation.getProxy().getConfig().getExceptionMappings();
            ExceptionMappingConfig mappingConfig =
this.findMappingFromExceptions(exceptionMappings, e);
            if (mappingConfig != null && mappingConfig.getResult() != null) {
                Map<String, String> mappingParams = mappingConfig.getParams();
                // create a mutable HashMap since some interceptors
will remove parameters, and parameterMap is immutable
                HttpParameters parameters =
HttpParameters.create(mappingParams).build();
                invocation.getInvocationContext().setParameters(parameters);
                result = mappingConfig.getResult();
                publishException(invocation, new ExceptionHolder(e));
            } else {
                throw e;
            }

        }

        return result;
    }
}


2018-09-30 01:47:45 548680269 [ajp-nio-8009-exec-10] ERROR
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor - Uncaught
error by user:xxxxx
java.lang.Exception: Uncaught error by user:xxxxx
at
com.afs.web.common.struts.interceptor.ExceptionInterceptor.intercept(ExceptionInterceptor.java:56)
at
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
at
com.afs.web.struts.interceptor.AccountInterceptor.intercept(AccountInterceptor.java:36)
at
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
at
com.afs.web.struts.interceptor.SessionInterceptor.intercept(SessionInterceptor.java:56)
at
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
at
com.afs.web.common.struts.interceptor.NoCacheInterceptor.intercept(NoCacheInterceptor.java:25)
at
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
at
org.apache.struts2.factory.StrutsActionProxy.execute(StrutsActionProxy.java:48)
at
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:574)
at
org.apache.struts2.dispatcher.ExecuteOperations.executeAction(ExecuteOperations.java:79)
at
org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:141)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320)
at
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
at
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:150)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:155)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66)
at
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
at
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
at
org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215)
at
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178)
at
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
at
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at
org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:185)
at
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:479)
at
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468)
at
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException: null

Re: Identifying cause of NPE in Struts ExceptionInterceptor

[Burton Rhodes <bu...@gmail.com>]

Never mind.  I was able to figure it out by using
"-XX:-OmitStackTraceInFastThrow"
in my jvm options.

On Sun, Sep 30, 2018 at 7:20 AM Burton Rhodes <bu...@gmail.com>
wrote:

> I am having trouble identifying where a NPE is being generated.  I have
> the exception stacktrace below with a non-descriptive line at the end.  Am
> I missing a vital line in the stacktrace or does anyone have an idea how I
> can log more information on this?
>
> [My ExceptionInterceptor.java]
>
> public class ExceptionInterceptor extends ExceptionMappingInterceptor {
>
>     @Override
>     public String intercept(ActionInvocation invocation) throws Exception {
>
>         String result;
>
>         try {
>             result = invocation.invoke();
>
>         } catch (Exception e) {
>
>             // Log exception
>             if (isLogEnabled()) {
>                 String userName = SecurityContextHolder.getContext().getAuthentication().getName();
>                 Exception ex = new Exception("Uncaught error by user:" + userName, e);
>                 handleLogging(ex);
>             }
>
>             List<ExceptionMappingConfig> exceptionMappings = invocation.getProxy().getConfig().getExceptionMappings();
>             ExceptionMappingConfig mappingConfig = this.findMappingFromExceptions(exceptionMappings, e);
>             if (mappingConfig != null && mappingConfig.getResult() != null) {
>                 Map<String, String> mappingParams = mappingConfig.getParams();
>                 // create a mutable HashMap since some interceptors will remove parameters, and parameterMap is immutable
>                 HttpParameters parameters = HttpParameters.create(mappingParams).build();
>                 invocation.getInvocationContext().setParameters(parameters);
>                 result = mappingConfig.getResult();
>                 publishException(invocation, new ExceptionHolder(e));
>             } else {
>                 throw e;
>             }
>
>         }
>
>         return result;
>     }
> }
>
>
> 2018-09-30 01:47:45 548680269 [ajp-nio-8009-exec-10] ERROR
> com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor - Uncaught
> error by user:xxxxx
> java.lang.Exception: Uncaught error by user:xxxxx
> at
> com.afs.web.common.struts.interceptor.ExceptionInterceptor.intercept(ExceptionInterceptor.java:56)
> at
> com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
> at
> com.afs.web.struts.interceptor.AccountInterceptor.intercept(AccountInterceptor.java:36)
> at
> com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
> at
> com.afs.web.struts.interceptor.SessionInterceptor.intercept(SessionInterceptor.java:56)
> at
> com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
> at
> com.afs.web.common.struts.interceptor.NoCacheInterceptor.intercept(NoCacheInterceptor.java:25)
> at
> com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
> at
> org.apache.struts2.factory.StrutsActionProxy.execute(StrutsActionProxy.java:48)
> at
> org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:574)
> at
> org.apache.struts2.dispatcher.ExecuteOperations.executeAction(ExecuteOperations.java:79)
> at
> org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:141)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320)
> at
> org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
> at
> org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:119)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:150)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:170)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:155)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66)
> at
> org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
> at
> org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
> at
> org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334)
> at
> org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215)
> at
> org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178)
> at
> org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:357)
> at
> org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:270)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
> at
> org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:185)
> at
> org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
> at
> org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
> at
> org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
> at
> org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496)
> at
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
> at
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
> at
> org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
> at
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
> at
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
> at org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:479)
> at
> org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
> at
> org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
> at
> org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468)
> at
> org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
> at
> org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
> at java.lang.Thread.run(Thread.java:748)
> Caused by: java.lang.NullPointerException: null
>