Spring websocket EOFException

Question

My project is using spring-boot web socket and embedded tomcat to implement chat server. Everything is ok but sometimes I got EOFException, and then the client cannot send a message to chat server until I restart tomcat then everything worked ok. I don't know when EOFException will happen. Pls help me

[TRACE] 2017-10-23 06:17:10.707 [http-nio-7755-exec-4] NativeWebSocketSession - Sending TextMessage payload=[{"result":..], byteCount=164, last=true], StandardWebSocketSession[id=42b, uri=/chat] [DEBUG] 2017-10-23 06:17:29.670 [http-nio-7755-exec-8] LoggingWebSocketHandlerDecorator - Transport error in StandardWebSocketSession[id=42b, uri=/chat] java.io.EOFException: null at org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper.fillReadBuffer(NioEndpoint.java:1242) ~[tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper.read(NioEndpoint.java:1182) ~[tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.tomcat.websocket.server.WsFrameServer.onDataAvailable(WsFrameServer.java:72) ~[tomcat-embed-websocket-8.5.16.jar!/:8.5.16] at org.apache.tomcat.websocket.server.WsFrameServer.doOnDataAvailable(WsFrameServer.java:171) ~[tomcat-embed-websocket-8.5.16.jar!/:8.5.16] at org.apache.tomcat.websocket.server.WsFrameServer.notifyDataAvailable(WsFrameServer.java:151) ~[tomcat-embed-websocket-8.5.16.jar!/:8.5.16] at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.upgradeDispatch(WsHttpUpgradeHandler.java:148) [tomcat-embed-websocket-8.5.16.jar!/:8.5.16] at org.apache.coyote.http11.upgrade.UpgradeProcessorInternal.dispatch(UpgradeProcessorInternal.java:54) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:53) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_131] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_131] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.16.jar!/:8.5.16] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131] [DEBUG] 2017-10-23 06:17:29.671 [http-nio-7755-exec-8] LoggingWebSocketHandlerDecorator - StandardWebSocketSession[id=42b, uri=/chat] closed with CloseStatus[code=1006, reason=null]

Answer 1

Yup, i solved it. This exception will happen after client or server was interrupted or stopped without calling close socket method(maybe lost internet, or shutdown laptop or mobile when using socket). So if we would like to solve this problem, we have to implement ping/pong mechanism, after interval if we cannot get pong response from client, we will close this socket. Another way, we can catch this exception, then we will close old socket.

Thanks, Andy