title: tomcat socketTimeout exception
body: <p>I am simulating ajax file download using iframe, the request goes to tomcat app(servlet) for a file download which is a time consuming process(might take more than 1 min), the issue is that after certain amount of time, either tomcat or the browser client terminates the connection.  see Tomcat exception below.  who is terminating it, client or server?   is there a way I can increase the timeout?</p>
  
  <pre>
  var iframe = document.createElement("iframe");
  
  iframe.src="http://xxxxxxxxx?";
  </pre>
  
  <pre>
  Caused by: ClientAbortException:  java.net.SocketException: Broken pipe
          at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:358)
          at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:434)
          at org.apache.tomcat.util.buf.ByteChunk.append(ByteChunk.java:349)
          at org.apache.catalina.connector.OutputBuffer.writeBytes(OutputBuffer.java:381)
          at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:370)
          at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:89)
          at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:83)
          at org.apache.poi.poifs.storage.BigBlock.doWriteData(BigBlock.java:55)
          at org.apache.poi.poifs.storage.DocumentBlock.writeData(DocumentBlock.java:220)
          at org.apache.poi.poifs.storage.BigBlock.writeBlocks(BigBlock.java:86)
          at org.apache.poi.poifs.filesystem.POIFSDocument$BigBlockStore.writeBlocks(POIFSDocument.java:603)
          at org.apache.poi.poifs.filesystem.POIFSDocument.writeBlocks(POIFSDocument.java:275)
          at org.apache.poi.poifs.filesystem.POIFSFileSystem.writeFilesystem(POIFSFileSystem.java:390)
          at org.apache.poi.hssf.usermodel.HSSFWorkbook.write(HSSFWorkbook.java:1168)
          at net.sf.jasperreports.engine.export.JRXlsExporter.closeWorkbook(JRXlsExporter.java:199)
          ... 17 more
  Caused by: java.net.SocketException: Broken pipe
          at java.net.SocketOutputStream.socketWrite0(Native Method)
          at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
  </pre>