default TRegionReplicaSet getRegionReplicaSet() {
    throw new UnsupportedOperationException(getClass().getName());
  }
@return Optional.empty() iff {@link #isStorageExecutor()} and all candidate replica locations
    are unreachable
iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/partition/ExecutorType.java