在Struts的Action继承类中用response.getOutputStream()实现文件的下载时，在返回的ActionForward类时报错

问题描述： 使用Struts1.3.8，在使用response.getOutputStream方法进行下载文件时，在页面点击下载或取消都会在Tomcat中报如下错误 java.net.SocketException: Connection reset by peer: socket write error at java.net.SocketOutputStream.socketWrite0(Native Method) at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92) at java.net.SocketOutputStream.write(SocketOutputStream.java:136) at org.apache.jk.common.ChannelSocket.send(ChannelSocket.java:407) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:599) at org.apache.jk.server.JkCoyoteHandler.doWrite(JkCoyoteHandler.java:216) at org.apache.coyote.Response.doWrite(Response.java:524) at org.apache.coyote.tomcat4.OutputBuffer.realWriteBytes(OutputBuffer.java:384) at org.apache.tomcat.util.buf.ByteChunk.append(ByteChunk.java:369) at org.apache.coyote.tomcat4.OutputBuffer.writeBytes(OutputBuffer.java:411) at org.apache.coyote.tomcat4.OutputBuffer.write(OutputBuffer.java:398) at org.apache.coyote.tomcat4.CoyoteOutputStream.write(CoyoteOutputStream.java:110) at jxl.write.biff.MemoryDataOutput.writeData(MemoryDataOutput.java:107) at jxl.write.biff.CompoundFile.writeExcelData(CompoundFile.java:505) at jxl.write.biff.CompoundFile.write(CompoundFile.java:455) at jxl.write.biff.File.close(File.java:120) at jxl.write.biff.WritableWorkbookImpl.close(WritableWorkbookImpl.java:447) at ext.teammax.partclassification.util.WriteDataToExcelUtil.saveWbook(WriteDataToExcelUtil.java:185) at ext.teammax.partclassification.util.ExportPartsToExcel.exportPartNoDrawingInfoToExcel(ExportPartsToExcel.java:98) at ext.teammax.partclassification.action.ExportPartNoDrawingInfoAction.execute(ExportPartNoDrawingInfoAction.java:72) at org.apache.struts.chain.commands.servlet.ExecuteAction.execute(ExecuteAction.java:58) at org.apache.struts.chain.commands.AbstractExecuteAction.execute(AbstractExecuteAction.java:67) at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:304) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913) at ext.teammax.web.servlet.WindchillActionServlet.process(WindchillActionServlet.java:73) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449) at javax.servlet.http.HttpServlet.service(HttpServlet.java:740) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562) at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619) at java.lang.Thread.run(Thread.java:534) 08:16:54,971 WARN AbstractExceptionHandler:95 - Unhandled exception org.apache.jasper.JasperException: getOutputStream() has already been called for this response at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:254) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684) at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:575) at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:498) at org.apache.struts.chain.commands.servlet.PerformForward.handleAsInclude(PerformForward.java:141) at org.apache.struts.chain.commands.servlet.PerformForward.perform(PerformForward.java:92) at org.apache.struts.chain.commands.AbstractPerformForward.execute(AbstractPerformForward.java:54) at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:304) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913) at ext.teammax.web.servlet.WindchillActionServlet.process(WindchillActionServlet.java:73) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449) at javax.servlet.http.HttpServlet.service(HttpServlet.java:740) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562) at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619) at java.lang.Thread.run(Thread.java:534) 08:16:55,080 WARN ExceptionCatcher:165 - Exception from exceptionCommand 'servlet-exception' org.apache.jasper.JasperException: getOutputStream() has already been called for this response at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:254) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684) at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:575) at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:498) at org.apache.struts.chain.commands.servlet.PerformForward.handleAsInclude(PerformForward.java:141) at org.apache.struts.chain.commands.servlet.PerformForward.perform(PerformForward.java:92) at org.apache.struts.chain.commands.AbstractPerformForward.execute(AbstractPerformForward.java:54) at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:304) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190) at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913) at ext.teammax.web.servlet.WindchillActionServlet.process(WindchillActionServlet.java:73) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449) at javax.servlet.http.HttpServlet.service(HttpServlet.java:740) at javax.servlet.http.HttpServlet.service(HttpServlet.java:853) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2415) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:171) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174) at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480) at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995) at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562) at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619) at java.lang.Thread.run(Thread.java:534) 2009/8/6 上午 08:16:55 org.apache.jk.server.JkCoyoteHandler action 嚴重的: Error in action code java.net.SocketException: Connection reset by peer: socket write error at java.net.SocketOutputStream.socketWrite0(Native Method) at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92) at java.net.SocketOutputStream.write(SocketOutputStream.java:136) at org.apache.jk.common.ChannelSocket.send(ChannelSocket.java:407) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:599) at org.apache.jk.server.JkCoyoteHandler.action(JkCoyoteHandler.java:372) at org.apache.coyote.Response.action(Response.java:222) at org.apache.coyote.Response.finish(Response.java:343) at org.apache.coyote.tomcat4.OutputBuffer.close(OutputBuffer.java:326) at org.apache.coyote.tomcat4.CoyoteResponse.finishResponse(CoyoteResponse.java:500) at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:224) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:261) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:360) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:604) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:562) at org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:679) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619) at java.lang.Thread.run(Thread.java:534) 问题解决：将自己继承自Action类的××action类中return为null,不要返回AcitionForward对象