@InterfaceAudience.Private
  static Map<byte[], DataBlockEncoding> createFamilyDataBlockEncodingMap(Configuration conf) {
    Map<byte[], String> stringMap =
      createFamilyConfValueMap(conf, DATABLOCK_ENCODING_FAMILIES_CONF_KEY);
    Map<byte[], DataBlockEncoding> encoderMap = new TreeMap<>(Bytes.BYTES_COMPARATOR);
    for (Map.Entry<byte[], String> e : stringMap.entrySet()) {
      encoderMap.put(e.getKey(), DataBlockEncoding.valueOf((e.getValue())));
    }
    return encoderMap;
  }
Runs inside the task to deserialize column family to data block encoding type map from the
configuration.
@param conf to read the serialized values from
@return a map from column family to HFileDataBlockEncoder for the configured data block type
        for the family
hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java