2017-07-04 11:09:35,604 ERROR .magnolia.ui.admincentral.AdmincentralErrorHandler: AdmincentralUI has encountered an unhandled exception.
java.lang.IllegalArgumentException: Expected String argument, but got null
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:145)
at info.magnolia.resources.app.workbench.ResourcesContainer.getItem(ResourcesContainer.java:137)
at com.vaadin.ui.AbstractSelect.getItem(AbstractSelect.java:751)
at com.vaadin.ui.Table.handleClickEvent(Table.java:3161)
at com.vaadin.ui.Table.changeVariables(Table.java:2952)
at com.vaadin.ui.TreeTable.changeVariables(TreeTable.java:431)
at info.magnolia.ui.vaadin.grid.MagnoliaTreeTable.changeVariables(MagnoliaTreeTable.java:86)
at com.vaadin.server.communication.ServerRpcHandler.changeVariables(ServerRpcHandler.java:637)
at com.vaadin.server.communication.ServerRpcHandler.handleInvocation(ServerRpcHandler.java:463)
at com.vaadin.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:412)
at com.vaadin.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:273)
at com.vaadin.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:90)
at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1414)
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:365)
at info.magnolia.ui.admincentral.AdmincentralVaadinServlet.service(AdmincentralVaadinServlet.java:146)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at info.magnolia.cms.filters.ServletDispatchingFilter.doFilter(ServletDispatchingFilter.java:148)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.CompositeFilter.doFilter(CompositeFilter.java:65)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.VirtualUriFilter.doFilter(VirtualUriFilter.java:69)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.module.cache.executor.Bypass.processCacheRequest(Bypass.java:58)
at info.magnolia.module.cache.executor.CompositeExecutor.processCacheRequest(CompositeExecutor.java:67)
at info.magnolia.module.cache.filter.CacheFilter.doFilter(CacheFilter.java:220)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.i18n.I18nContentSupportFilter.doFilter(I18nContentSupportFilter.java:89)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.RangeSupportFilter.doFilter(RangeSupportFilter.java:77)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.security.BaseSecurityFilter.doFilter(BaseSecurityFilter.java:57)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.security.SecurityCallbackFilter.doFilter(SecurityCallbackFilter.java:84)
at info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:59)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.security.LogoutFilter.doFilter(LogoutFilter.java:94)
at info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:59)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.module.site.filters.SiteMergeFilter.doFilter(SiteMergeFilter.java:119)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.multisite.filters.MultiSiteFilter.doFilter(MultiSiteFilter.java:110)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MultiChannelFilter.doFilter(MultiChannelFilter.java:83)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.module.cache.filter.GZipFilter.doFilter(GZipFilter.java:73)
at info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:59)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.security.auth.login.LoginFilter.doFilter(LoginFilter.java:127)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.enterprise.registration.RegistrationFilter.doFilter(RegistrationFilter.java:64)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.personalization.preview.filter.PreviewFilter.doFilter(PreviewFilter.java:92)
at info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter.doFilter(OncePerRequestAbstractMgnlFilter.java:59)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:81)
at info.magnolia.cms.filters.ContentTypeFilter.doFilter(ContentTypeFilter.java:155)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.ContextFilter.doFilter(ContextFilter.java:128)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:79)
at info.magnolia.cms.filters.CompositeFilter.doFilter(CompositeFilter.java:65)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:85)
at info.magnolia.cms.filters.SafeDestroyMgnlFilterWrapper.doFilter(SafeDestroyMgnlFilterWrapper.java:107)
at info.magnolia.cms.filters.MgnlFilterDispatcher.doDispatch(MgnlFilterDispatcher.java:67)
at info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:108)
at info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:94)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:784)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:802)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1410)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)