public Optional<TConsensusGroupType> getRegionType(int regionId) {
    return partitionInfo.getRegionType(regionId);
  }
Get the {@link TConsensusGroupType} of the given integer regionId.

@param regionId The specified integer regionId
@return {@link Optional#of(Object tConsensusGroupType)} of the given integer regionId, or
    {@link Optional#empty()} if the integer regionId does not match any of the regionGroups.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/manager/partition/PartitionManager.java