Error while selecting sub page

Hi All,

I use openhab 1.8.3 on a rasberry pi 2B.

When openhab runs for some days, it suddenly reports an error when I try to enter a sub page (but only 1 specific one, all others are working: the structure is:

  • main page with an outdoor subpage, basement, first floor, second floor and status
  • all of the have subpages where you can choose the different rooms
  • the rooms have subpages for temperature, humidity and some other stuff.

the error when clicking on the first floor room ‘bath room’ is:

=============
2017-04-19 14:44:10.077 [WARN ] [e.jetty.servlet.ServletHandler] - /openhab.app
java.lang.NullPointerException: null
at org.openhab.ui.internal.items.ItemUIRegistryImpl.getIcon(ItemUIRegistryImpl.java:409) ~[na:na]
at org.openhab.ui.webapp.internal.render.TextRenderer.renderWidget(TextRenderer.java:44) ~[na:na]
at org.openhab.ui.webapp.internal.render.PageRenderer.renderWidget(PageRenderer.java:158) ~[na:na]
at org.openhab.ui.webapp.internal.render.PageRenderer.processChildren(PageRenderer.java:121) ~[na:na]
at org.openhab.ui.webapp.internal.render.PageRenderer.processPage(PageRenderer.java:86) ~[na:na]
at org.openhab.ui.webapp.internal.servlet.WebAppServlet.service(WebAppServlet.java:143) ~[na:na]
at org.eclipse.equinox.http.servlet.internal.ServletRegistration.service(ServletRegistration.java:61) ~[na:na]
at org.eclipse.equinox.http.servlet.internal.ProxyServlet.processAlias(ProxyServlet.java:128) ~[na:na]
at org.eclipse.equinox.http.servlet.internal.ProxyServlet.service(ProxyServlet.java:60) ~[na:na]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:848) ~[javax.servlet_3.0.0.v201112011016.jar:na]
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:598) ~[org.eclipse.jetty.servlet_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:486) [org.eclipse.jetty.servlet_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1065) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:413) [org.eclipse.jetty.servlet_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:999) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:250) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:149) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:111) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.Server.handle(Server.java:350) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:454) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:890) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:944) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:630) [org.eclipse.jetty.http_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:230) [org.eclipse.jetty.http_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:77) [org.eclipse.jetty.server_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:606) [org.eclipse.jetty.io_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:46) [org.eclipse.jetty.io_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:603) [org.eclipse.jetty.util_8.1.3.v20120522.jar:8.1.3.v20120522]
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:538) [org.eclipse.jetty.util_8.1.3.v20120522.jar:8.1.3.v20120522]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_65]

=============
As said: when I reboot, it is fixed but I don’t know what is causing it. Please help!