code: private void processChallenges(
        final Map<String, Header> challenges,
        final AuthState authState,
        final AuthenticationHandler authHandler,
        final HttpResponse response,
        final HttpContext context)
          throws MalformedChallengeException, AuthenticationException {
  
      AuthScheme authScheme = authState.getAuthScheme();
      if (authScheme == null) {
        // Authentication not attempted before
        authScheme = authHandler.selectScheme(challenges, response, context);
        authState.setAuthScheme(authScheme);
      }
      String id = authScheme.getSchemeName();
  
      Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
      if (challenge == null) {
        throw new AuthenticationException(id +
          " authorization challenge expected, but not found");
      }
      authScheme.processChallenge(challenge);
      this.log.debug("Authorization challenge processed");
    }
docs: abortConnection