Java Programming

import java.io.IOException;
	import java.io.OutputStream;
	 
	import javax.servlet.ServletException;
	import javax.servlet.http.HttpServlet;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;
	 
	import jxl.Workbook;
	import jxl.write.Label;
	import jxl.write.WritableSheet;
	import jxl.write.WritableWorkbook;
	 
	public class Sample extends HttpServlet
	{
	 public void doGet(HttpServletRequest request, HttpServletResponse response)
	 throws ServletException, IOException
	 {
	  OutputStream out = null;
	  try
	  {
	   response.setContentType("application/vnd.ms-excel");
	   response.setHeader("Content-Disposition", "attachment; filename=sampleName.xls");
	   WritableWorkbook w = Workbook.createWorkbook(response.getOutputStream());
	   WritableSheet s = w.createSheet("Demo", 0);
	   s.addCell(new Label(0, 0, "Hello World"));
	   w.write();
	   w.close();
	  } catch (Exception e)
	  {
	   throw new ServletException("Exception in Excel Sample Servlet", e);
	  } finally
	  {
	   if (out != null)
	    out.close();
	  }
	 }
	}

I am trying to create a generic class that can export database table to excel files. But the problem is Workbook.createWorkbook(OuputStream) only take in outputstream. I can't pass the outputstream over to servlet for the user to download.

Anyone can help?