我在使用Spring(5.2.0)发布STOMP消息时,偶尔会遇到一些NPE.不幸的是,我不能准确地提供重现的步骤,但我希望得到一些关于如何发生这种情况的见解。
我查看了源码,我唯一能想到的是通道为空。我希望得到一个确认和可能的原因,或者一个替代的解释。
客户端没有断开连接,但似乎这个错误会导致客户端断开连接,因为它收到了1002代码。
附上的是堆栈跟踪。任何帮助或见解将非常感激。谢谢!我正在遇到一些偶尔出现的NPC错误。
org.springframework.messaging.MessageDeliveryException: Failed to send message to ExecutorSubscribableChannel[clientInboundChannel]; nested exception is java.lang.NullPointerException
at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:146)
at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:122)
at org.springframework.web.socket.messaging.StompSubProtocolHandler.handleMessageFromClient(StompSubProtocolHandler.java:302)
at org.springframework.web.socket.messaging.SubProtocolWebSocketHandler.handleMessage(SubProtocolWebSocketHandler.java:335)
at org.springframework.web.socket.handler.WebSocketHandlerDecorator.handleMessage(WebSocketHandlerDecorator.java:75)
at org.springframework.web.socket.handler.LoggingWebSocketHandlerDecorator.handleMessage(LoggingWebSocketHandlerDecorator.java:56)
at org.springframework.web.socket.handler.ExceptionWebSocketHandlerDecorator.handleMessage(ExceptionWebSocketHandlerDecorator.java:58)
at org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter.handleTextMessage(StandardWebSocketHandlerAdapter.java:114)
at org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter.access$000(StandardWebSocketHandlerAdapter.java:43)
at org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter$3.onMessage(StandardWebSocketHandlerAdapter.java:85)
at org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter$3.onMessage(StandardWebSocketHandlerAdapter.java:82)
at org.apache.tomcat.websocket.WsFrameBase.sendMessageText(WsFrameBase.java:395)
at org.apache.tomcat.websocket.server.WsFrameServer.sendMessageText(WsFrameServer.java:119)
at org.apache.tomcat.websocket.WsFrameBase.processDataText(WsFrameBase.java:495)
at org.apache.tomcat.websocket.WsFrameBase.processData(WsFrameBase.java:294)
at org.apache.tomcat.websocket.WsFrameBase.processInputBuffer(WsFrameBase.java:133)
at org.apache.tomcat.websocket.server.WsFrameServer.onDataAvailable(WsFrameServer.java:82)
at org.apache.tomcat.websocket.server.WsFrameServer.doOnDataAvailable(WsFrameServer.java:171)
at org.apache.tomcat.websocket.server.WsFrameServer.notifyDataAvailable(WsFrameServer.java:151)
at org.apache.tomcat.websocket.server.WsHttpUpgradeHandler.upgradeDispatch(WsHttpUpgradeHandler.java:148)
at org.apache.coyote.http11.upgrade.UpgradeProcessorInternal.dispatch(UpgradeProcessorInternal.java:54)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:53)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1579)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException: null
at org.springframework.messaging.support.AbstractMessageChannel$ChannelInterceptorChain.applyPreSend(AbstractMessageChannel.java:178)
at org.springframework.messaging.support.AbstractMessageChannel.send(AbstractMessageChannel.java:132)
... 28 common frames omitted```
与这个问题无关;但你应该试着跟上维护版本;当前的5.2.x版本是5.2.6。
NPE意味着你以某种方式结束了与 null
中的拦截器列表。
抽象通道中的第178行正在调用列表中的每个拦截器。
我想你能在那里获得NPE的唯一方法是你已经(或某些东西)添加了 null
到名单上。
for (ChannelInterceptor interceptor : interceptors) {
Message<?> resolvedMessage = interceptor.preSend(messageToUse, channel); // line 178
if (resolvedMessage == null) {
...