是什么导致我的java.net.SocketException：连接重置？

Question

我们java.net.SocketException: Connection reset在日志中看到频繁但间歇的 错误。我们不确定Connection reset错误的真正来源以及调试方法。

该问题似乎与我们尝试发送的消息无关。请注意，该消息不是 connection reset by peer。

关于此异常的典型原因是什么以及如何进行的任何建议？

这是一个代表性的堆栈跟踪（com.companyname.mtix.sms是我们的组件）：

java.net.SocketException：连接重置
    java.net.SocketException: Connection reset
        at java.net.SocketInputStream.read(SocketInputStream.java:168)
        at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:235)
        at org.apache.commons.httpclient.HttpParser.readRawLine(HttpParser.java:77)
        at org.apache.commons.httpclient.HttpParser.readLine(HttpParser.java:105)
        at org.apache.commons.httpclient.HttpConnection.readLine(HttpConnection.java:1115)
        at org.apache.commons.httpclient.HttpMethodBase.readStatusLine(HttpMethodBase.java:1832)
        at org.apache.commons.httpclient.HttpMethodBase.readResponse(HttpMethodBase.java:1590)
        at org.apache.commons.httpclient.HttpMethodBase.execute(HttpMethodBase.java:995)
        at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:397)
        at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:170)
        at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:396)
        at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:324)
        at com.companyname.mtix.sms.services.impl.message.SendTextMessage.sendTextMessage(SendTextMessage.java:127)
        at com.companyname.mtix.sms.services.MessageServiceImpl.sendTextMessage(MessageServiceImpl.java:125)
        at com.companyname.mtix.sms.services.remote.MessageServiceRemoteImpl.sendTextMessage(MessageServiceRemoteImpl.java:43)
        at sun.reflect.GeneratedMethodAccessor203.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at org.apache.axis.providers.java.RPCProvider.invokeMethod(RPCProvider.java:397)
        at org.apache.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:186)
        at org.apache.axis.providers.java.JavaProvider.invoke(JavaProvider.java:323)
        at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:32)
        at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
        at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
        at org.apache.axis.handlers.soap.SOAPService.invoke(SOAPService.java:453)
        at org.apache.axis.server.AxisServer.invoke(AxisServer.java:281)
        at org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:699)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
        at org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase.java:327)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.companyname.mtix.sms.http.filters.NoCacheFilter.doFilter(NoCacheFilter.java:63)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at com.companyname.mtix.sms.http.filters.MessageFilter.doFilter(MessageFilter.java:53)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:61)
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:77)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.ajaxanywhere.AAFilter.doFilter(AAFilter.java:46)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
        at java.lang.Thread.run(Thread.java:595)

我们的组件是一个在Tomcat下运行的Web应用程序，该应用程序调用发送SMS消息的第三方Web服务，这种情况经常发生。引发异常的代码行是下面的代码片段的最后一行。

String aggregatorResponse = null;
HttpClient httpClient = prepareHttpClient( username, password );
PostMethod postMethod = preparePostMethod( textUrl );

try {
  SybaseTextMessageBuilder builder = new SybaseTextMessageBuilder();
  URL notifyUrl = buildNotificationUrl( textMessage, codeSetManager );
  String smsRequestDocument = builder.buildTextMessage( textMessage, notifyUrl );
  LOG.debug( "Sybase MT document created as: \n" + smsRequestDocument );

  postMethod.setRequestEntity( new StringRequestEntity( smsRequestDocument ) );
  LOG.debug( "commiting SMS to aggregator: " + textMessage.toString() );
  int httpStatus = httpClient.executeMethod( postMethod );

Answer 1

SocketException的Javadoc指出它是

引发以表明基础协议中存在错误，例如TCP错误

在您的情况下，连接似乎已被连接的服务器端关闭。这可能是您发送的请求有问题，也可能是问题的解决。

为了帮助调试，您可以看一下使用诸如Wireshark之​​类的工具来查看实际的网络数据包。另外，您是否可以使用Java代码的替代客户端来测试Web服务？如果成功，则表明Java代码存在错误。

当您使用Commons HTTP Client时，请查看一下Common HTTP Client Logging Guide。这将告诉您如何在HTTP级别记录请求。