void okReply(HttpTransaction req) throws IOException {
req.setResponseEntityBody("Hello .");
req.sendResponse(200, "Ok");
req.orderlyClose();
}
void errorReply(HttpTransaction req, String reply) throws IOException {
req.addResponseHeader("Connection", "close");
req.addResponseHeader("Www-authenticate", reply);
req.sendResponse(401, "Unauthorized");
req.orderlyClose();
}