How to download a file via Portlet Bridge in JBoss EPP 5?

Issue

• How to stream a file out from portlet in JBoss EPP 5.

• The code works well in seam application but doesn't in portlet using Portlet Bridge.

  public void dumpToClient(StringWriter stream, String fileName)
    throws Exception {
  
     HttpServletResponse response = this.getResponse();
  
     HttpServletRequest request = this.getRequest();
  
     String charset = ProtoConst.CSV_CHARSET;
  
     String browserType = request.getHeader("user-agent");
     if ((null != browserType) && (-1 != browserType.indexOf("MSIE"))) {
       fileName = URLEncoder.encode(fileName, "UTF-8");
     } else if ((null != browserType)
         && (-1 != browserType.indexOf("Mozilla"))) {
       fileName = new String(fileName.getBytes("UTF-8"), "UTF-8");
  
     }
  
     response.reset();
     response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
     response.setContentType("application/octet-stream;charset="
       + charset.trim());
     PrintWriter out = response.getWriter();
     out.print(stream.toString());
     out.flush();
  
     FacesContext.getCurrentInstance().responseComplete();
  }