protected Set<String> getEnabledServices(String categoryName, String manageServicesConfigurationPropertyName, String enabledServicesPropertyName) {
    final Map<String, String> configurationProperties = getConfigurationProperties(categoryName);
    final boolean manageConfigurations = StringUtils.isNotBlank(manageServicesConfigurationPropertyName)
        && "true".equalsIgnoreCase(configurationProperties.get(manageServicesConfigurationPropertyName));
    final String enabledServices = (manageConfigurations) ? configurationProperties.get(enabledServicesPropertyName) : null;

    if (StringUtils.isEmpty(enabledServices)) {
      return Collections.emptySet();
    } else {
      return Arrays.stream(enabledServices.split(",")).map(String::trim).map(String::toUpperCase).collect(Collectors.toSet());
    }
  }
Get the properties associated with a configuration category

@param categoryName the name of the requested category
@return a map of property names to values; or null if the data does not exist
ambari-server/src/main/java/org/apache/ambari/server/controller/internal/AmbariServerConfigurationHandler.java