wssessionlistener-stacktrace.md

Jun 25, 2014 11:34:19 AM org.apache.catalina.session.StandardSession expire
SEVERE: Session event listener threw exception
java.lang.NullPointerException
	at org.apache.tomcat.websocket.server.WsServerContainer.unregisterAuthenticatedSession(WsServerContainer.java:367)
	at org.apache.tomcat.websocket.server.WsServerContainer.unregisterSession(WsServerContainer.java:344)
	at org.apache.tomcat.websocket.WsSession.sendCloseMessage(WsSession.java:494)
	at org.apache.tomcat.websocket.WsSession.doClose(WsSession.java:417)
	at org.apache.tomcat.websocket.WsSession.close(WsSession.java:394)
	at org.apache.tomcat.websocket.server.WsServerContainer.closeAuthenticatedSession(WsServerContainer.java:377)
	at org.apache.tomcat.websocket.server.WsSessionListener.sessionDestroyed(WsSessionListener.java:40)
	at org.apache.catalina.session.StandardSession.expire(StandardSession.java:808)
	at org.apache.catalina.session.StandardSession.isValid(StandardSession.java:658)
	at org.apache.catalina.session.ManagerBase.processExpires(ManagerBase.java:534)
	at org.apache.catalina.session.ManagerBase.backgroundProcess(ManagerBase.java:519)
	at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1352)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1530)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
	at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1519)
	at java.lang.Thread.run(Thread.java:744)

11:34:20 [clientOutboundChannel-9] WebSocketServerSockJsSession - Terminating connection after failure to send message to client.
java.lang.IllegalArgumentException: Cannot send message after connection closed.
	at org.springframework.util.Assert.isTrue(Assert.java:65)
	at org.springframework.web.socket.adapter.AbstractWebSocketSession.sendMessage(AbstractWebSocketSession.java:97)
	at org.springframework.web.socket.sockjs.transport.session.WebSocketServerSockJsSession.writeFrameInternal(WebSocketServerSockJsSession.java:196)
	at org.springframework.web.socket.sockjs.transport.session.AbstractSockJsSession.writeFrame(AbstractSockJsSession.java:336)
	at org.springframework.web.socket.sockjs.transport.session.WebSocketServerSockJsSession.sendMessageInternal(WebSocketServerSockJsSession.java:186)
	at org.springframework.web.socket.sockjs.transport.session.AbstractSockJsSession.sendMessage(AbstractSockJsSession.java:251)
	at org.springframework.web.socket.handler.ConcurrentWebSocketSessionDecorator.tryFlushMessageBuffer(ConcurrentWebSocketSessionDecorator.java:126)
	at org.springframework.web.socket.handler.ConcurrentWebSocketSessionDecorator.sendMessage(ConcurrentWebSocketSessionDecorator.java:99)
	at org.springframework.web.socket.messaging.StompSubProtocolHandler.handleMessageToClient(StompSubProtocolHandler.java:327)
	at org.springframework.web.socket.messaging.SubProtocolWebSocketHandler.handleMessage(SubProtocolWebSocketHandler.java:305)
	at org.springframework.messaging.support.ExecutorSubscribableChannel$1.run(ExecutorSubscribableChannel.java:70)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)

Hi, Rob! This gist is pretty old, but anyway, have you managed to fix this problem in a some way?