下载异常java.io.IOException: Connection reset by peer

文件下载异常：Caused by: java.io.IOException: Connection reset by peer

信息:所在IP:192.168.5.92所在系统:null接口 [/api/v2/flexible-insure/grp/downloadFileForGrp] 出现异常，方法：controller.FcGrpDoController$$EnhancerBySpringCGLIB$$d4a3992a.downloadFile，异常摘要：java.io.IOException: Connection reset by peer^M
异常堆栈:org.apache.catalina.connector.ClientAbortException: java.io.IOException: Connection reset by peer
        at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:356)
        at org.apache.catalina.connector.OutputBuffer.flushByteBuffer(OutputBuffer.java:825)
        at org.apache.catalina.connector.OutputBuffer.append(OutputBuffer.java:730)
        at org.apache.catalina.connector.OutputBuffer.writeBytes(OutputBuffer.java:391)
        at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:369)
        at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:96)
        at org.springframework.util.StreamUtils.copy(StreamUtils.java:140)
        at org.springframework.http.converter.ResourceHttpMessageConverter.writeContent(ResourceHttpMessageConverter.java:132)
        at org.springframework.http.converter.ResourceHttpMessageConverter.writeInternal(ResourceHttpMessageConverter.java:124)
        at org.springframework.http.converter.ResourceHttpMessageConverter.writeInternal(ResourceHttpMessageConverter.java:45)
        at org.springframework.http.converter.AbstractHttpMessageConverter.write(AbstractHttpMessageConverter.java:224)
        at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:275)
        at org.springframework.web.servlet.mvc.method.annotation.HttpEntityMethodProcessor.handleReturnValue(HttpEntityMethodProcessor.java:224)
        at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:82)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:119)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
        at org.springframework.web.servlet.FrameworkServlet.proce***equest(FrameworkServlet.java:974)
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
Caused by: java.io.IOException: Connection reset by peer
        at sun.nio.ch.FileDispatcherImpl.write0(Native Method)
        at sun.nio.ch.SocketDispatcher.write(SocketDispatcher.java:47)
        at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93)
        at sun.nio.ch.IOUtil.write(IOUtil.java:65)
        at sun.nio.ch.SocketChannelImpl.write(SocketChannelImpl.java:471)
        at org.apache.tomcat.util.net.NioChannel.write(NioChannel.java:134)
        at org.apache.tomcat.util.net.NioBlockingSelector.write(NioBlockingSelector.java:101)
        at org.apache.tomcat.util.net.NioSelectorPool.write(NioSelectorPool.java:157)
	```
问题分析：
	1、客户端再发起请求后没有等服务器端相应完，点击了stop按钮，导致服务器端接收到取消请求（频繁的刷新就会产生此问题）。
   通常情况下是不会有这么无聊的用户，出现这种情况可能是由于用户提交了请求，服务器端相应缓慢，比如业务逻辑有问题等原因，导致页面过了很久也没有刷新出来，用户就有可能取消或重新发起请求。
这种错误是合理范围内的，无法避免的，不必关心它。
2、Tomcat服务器在接受用户请求的时候，有其自身的处理能力，线程、服务器等各个资源限制，超出Tomcat承载范围的请求，就会被tomcat停掉，也可能产生该错误。
3、Linux的线程机制会产生JVM出错的问题，特别是在连接高峰期间经常出现这样的问题，tomcat在linux下也出现类似情况。
查看调用日志

@@[2021-02-23 16:02:19.020] [92] [http-nio-8098-exec-5] [ERROR] @@[2021-02-23 16:02:19.027] [92] [http-nio-8098-exec-5] [ERROR] @@[2021-02-23 16:02:19.030] [92] [http-nio-8098-exec-5] [ERROR] @@[2021-02-23 16:02:19.571] [88] [http-nio-8098-exec-1] [ERROR]

发现确实是重复多次点击请求异常。