[2020-01-10 15:39:44,727] [HTTP-80] ERROR com.google.gerrit.pgm.http.jetty.HiddenErrorHandler : Error in GET /r/
com.google.inject.ProvisionException: Unable to provision, see the following errors:

1) Error injecting constructor, java.lang.NullPointerException
  at com.googlesource.gerrit.plugins.websession.flatfile.FlatFileWebSession.<init>(FlatFileWebSession.java:55)
  at com.googlesource.gerrit.plugins.websession.flatfile.FlatFileWebSession.class(FlatFileWebSession.java:55)
  while locating com.googlesource.gerrit.plugins.websession.flatfile.FlatFileWebSession
  at com.google.gerrit.extensions.registration.DynamicItem.bind(DynamicItem.java:110)
  while locating com.google.gerrit.httpd.WebSession
  at com.google.gerrit.server.util.ThreadLocalRequestContext$1.provideCurrentUser(ThreadLocalRequestContext.java:55) (via modules: com.google.gerrit.server.config.GerritGlobalModule -> com.google.gerrit.server.util.ThreadLocalRequestContext$1)
  while locating com.google.gerrit.server.CurrentUser

1 error
        at com.google.inject.internal.InternalProvisionException.toProvisionException(InternalProvisionException.java:226)
        at com.google.inject.internal.InjectorImpl$1.get(InjectorImpl.java:1053)
        at com.google.gerrit.httpd.GetUserFilter.doFilter(GetUserFilter.java:82)
        at com.google.gerrit.httpd.RunAsFilter.doFilter(RunAsFilter.java:120)
        at com.google.gerrit.httpd.AllRequestFilter$FilterProxy$1.doFilter(AllRequestFilter.java:133)
        at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:239)
        at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:215)
        at com.googlesource.gerrit.plugins.javamelody.GerritMonitoringFilter.doFilter(GerritMonitoringFilter.java:66)
        at com.google.gerrit.httpd.AllRequestFilter$FilterProxy$1.doFilter(AllRequestFilter.java:129)
        at com.google.gerrit.httpd.AllRequestFilter$FilterProxy.doFilter(AllRequestFilter.java:135)
        at com.google.gerrit.httpd.RequestCleanupFilter.doFilter(RequestCleanupFilter.java:60)
        at com.google.gerrit.httpd.RequestMetricsFilter.doFilter(RequestMetricsFilter.java:57)
        at com.google.gerrit.httpd.RequestContextFilter.doFilter(RequestContextFilter.java:64)
        at com.google.inject.servlet.ManagedFilterPipeline.dispatch(ManagedFilterPipeline.java:121)
        at com.google.inject.servlet.GuiceFilter.doFilter(GuiceFilter.java:133)
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1604)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:545)
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1607)
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1297)
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188)
        ......