code: protected void writeOutput(HttpServletResponse response, String output) throws ServletException, IOException {
          response.getWriter().print(output);
          response.getWriter().flush();
      }
docs: Writes the encoded outgoing commands to the {@code response}.
  
  @param response -  an HttpServletResponse object that contains the response the servlet sends to the client
  @param output   - the encoded collection of commands to be sent back to the client
  
  @throws IOException      - if an input or output error is detected when the servlet handles the request
  @throws ServletException - if the request for the POST could not be handled