SocketTimeoutException Timeout on read

Does anybody knows where this come from
org.atmosphere.container.Jetty9WebSocketHandler onWebSocketError
SEVERE: {}
java.net.SocketTimeoutException: Timeout on Read
    at org.eclipse.jetty.websocket.common.io.AbstractWebSocketConnection.onReadTimeout(AbstractWebSocketConnection.java:526)?

You're using Push on Jetty9, thus the browser upgrades the http communication to websocket eventually. When the browser is closed, the websocket TCP/IP connection is closed as well. I'm guessing that Jetty for some reason doesn't receive the TCP close, thinks that the websocket connection is opened yet receives no heartbeat and thus complains.
Can you observe when exactly this exception occurs?
I vaguely remember having those exceptions on regular basis with Jetty, yet they were gone with Tomcat. I remember they were quite harmless. Maybe upgrading Jetty could help.

Yes, I am using jetty inside Eclipse. I guess that it is problem only with jetty but I don't know if I am right or if problem persist on Tomcat - if it doesn't then it's ok. I couldn't catch when this happens but browser (chrome) wasn't close... thanks