Java servlet to send audio file

Question

Hi, I have used the example in this link http://www.java2s.com/Code/Java/Servlets/Sendmp3.htm to send a wav file to the client. I have changed the content type to audio/x-wav as I am sending a wav file not mp3 as in the example.
For some reason, it seems to send something back, but the audio file does not have any data in it (0 bytes). Eg try this link to see what happens: http://mel.our-lan.com/?=barcode50214561353872
The file browser opens up winamp/media player, but the file has no data in it. Can anybody see the problem in my code?:
String fileName = "";
                    while (rs.next())
                         fileName = rs.getString("SoundClip");
                    if (fileName == null || fileName.equals(""))
                         throw new ServletException(
                           "Invalid or non-existent file parameter in barcodeServlet.");
                    String wavDir = ("http://mel.our-lan.com/wav-dir/" + fileName);
                         /*getServletContext().getInitParameter("wav-dir");*/
                    if (wavDir == null || wavDir.equals(""))
                      throw new ServletException(
                           "Invalid or non-existent wavDir context-param.");
                    ServletOutputStream stream = null;
                    BufferedInputStream buf = null;
                    try
                         stream = response.getOutputStream();
                         File wav = new File(wavDir + "/" + fileName);
                         //set response headers
                         response.setContentType("audio/x-wav");
                         response.addHeader("Content-Disposition", "attachment; filename="
                              + fileName);
                         response.setContentLength((int)wav.length());
                         FileInputStream input = new FileInputStream(wav);
                         byte[] buf1 = new byte[1024];
                         int len;
                         while ((len = input.read(buf1)) > 0)
                              stream.write(buf1, 0, len);
                         /* TRIED THE FOLLOWING ASWELL BUT SAME RESULT:
                                        buf = new BufferedInputStream(input);
                         int readBytes = 0;
                         //read from the file; write to the ServletOutputStream
                         while ((readBytes = buf.read()) != -1)
                              stream.write(readBytes);*/
                         input.close();
                    catch (IOException ioe)
                         throw new ServletException(ioe.getMessage());
                    finally
                         if (stream != null)
                              stream.close();
                         if (buf != null)
                              buf.close();
                    }

Answer 1

I tried the link; got the following:
java.lang.NullPointerException
     BarcodeServlet.doPost(BarcodeServlet.java:23)
     BarcodeServlet.doGet(BarcodeServlet.java:17)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:803)Take a look at this example, [1],might help you some.
[1] http://balusc.blogspot.com/2007/07/fileservlet.html
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