Java.io.IOException: Cannot close the same input stream twice

Question

I m writing a servlet that trigger by java URLConnection. Below is my code.
When i use request.getParameter I encounter Exception but if i remove my request.getParameter. is run without Exception.
Thank You
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
String nnfileName = request.getParameter("FileName");
try
InputStream is = request.getInputStream();
File thisFile = new File("../webapps/chunb/MonitorTool.zip");
FileOutputStream fileOut = new FileOutputStream(thisFile);
copy(is, fileOut);
is.close();
fileOut.flush();
fileOut.close();
catch (Exception e)
System.out.println("Exception in reading Input :" + e.toString());
}

Answer 1

I m not sure which line that throws the Exception, but if i remove the request.getPArameter the code work fine.
Anyone have this problem before???
Thank.