public void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws IOException, ServletException {
    if (eventHandler != null) {
      eventHandler.beforeAttemptAuthentication(this, httpServletRequest, httpServletResponse);
    }

    super.doFilterInternal(httpServletRequest, httpServletResponse, filterChain);
  }
Checks whether the authentication information is filled. If it is not, then a login failed audit event is logged

@param httpServletRequest  the request
@param httpServletResponse the response
@param filterChain         the Spring filter chain
@throws IOException
@throws ServletException
ambari-server/src/main/java/org/apache/ambari/server/security/authentication/AmbariBasicAuthenticationFilter.java