public String getKerberosEnabledTest() {
    return kerberosEnabledTest;
  }
Gets the JSON predicate ({@link PredicateUtils#fromJSON(String)} that can be used to determine
if Kerberos has been enabled for this service or not.

@return a valid JSON predicate ({@link PredicateUtils#fromJSON(String)}
ambari-server/src/main/java/org/apache/ambari/server/state/ServiceInfo.java