@Override
    protected void onError(final RequestContext requestContext) {
        WebUtils.addErrorMessageToContext(requestContext, AUTHN_FAILURE_MESSAGE_CODE);
    }
Abstract class to handle the retrieval and authentication of non-interactive
credential such as client certificates, NTLM, etc.

@author Scott Battaglia
@since 3.0.0
core/cas-server-core-webflow-api/src/main/java/org/apereo/cas/web/flow/actions/AbstractNonInteractiveCredentialsAction.java