private CodeFragmentManager codeFragmentManager;
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String id = request.getParameter("id");
CodeFragment c = codeFragmentManager.getCodeFragment(id);
String fileName = c.getUser() + "." + c.getLanguage();
String txt = c.getText();
response.setContentType("text/plain");
response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
response.setContentLength(txt.length());