code: public static void setGenericConf(Configuration conf,
        String nameserviceId, String... keys) {
      for (String key : keys) {
        String value = conf.get(getNameServiceIdKey(key, nameserviceId));
        if (value != null) {
          conf.set(key, value);
        }
      }
    }
docs: Sets the node specific setting into generic configuration key. Looks up
  value of "key.nameserviceId" and if found sets that value into generic key
  in the conf. Note that this only modifies the runtime conf.
  
  @param conf
  Configuration object to lookup specific key and to set the value
  to the key passed. Note the conf object is modified.
  @param nameserviceId
  nameservice Id to construct the node specific key.
  @param keys
  The key for which node specific value is looked up