public List<String> getActions(String serviceName) {
    List<String> result = serviceActions.get(serviceName.toLowerCase());
    if (result != null) {
      return result;
    } else {
      return Collections.emptyList();
    }
  }
Contains metadata about actions supported by services
ambari-server/src/main/java/org/apache/ambari/server/metadata/ActionMetadata.java