public void tryBuildRestAuthenticator(final Map<String, Authenticator> authenticators) {
        for (var i = 0; i <= MAX_NUM_AUTHENTICATORS; i++) {
            val url = getProperty(REST_URL, i);
            if (StringUtils.isNotBlank(url)) {
                authenticators.put(concat("rest", i), new RestAuthenticator(url));
            }
        }
    }
<p>tryBuildRestAuthenticator.</p>

@param authenticators a {@link Map} object
pac4j-config/src/main/java/org/pac4j/config/builder/RestAuthenticatorBuilder.java