// Handle pre-authenticated request
if (authenticator != null) {
// User authenticator.
user = authenticator.authenticate(realm, pathInContext, request, response);
} else {
// don't know how authenticate
log.warn("Mis-configured Authenticator for " + request.getPath());
throw new HttpException(HttpResponse.__500_Internal_Server_Error, "Mis-configured Authenticator for " + request.getPath());
}