public static ChecksumType getDefaultChecksumType() {
    return ChecksumType.CRC32C;
  }
Checksum types. The Checksum type is a one byte number that stores a representation of the
checksum algorithm used to encode a hfile. The ordinal of these cannot change or else you risk
breaking all existing HFiles out there.
hbase-common/src/main/java/org/apache/hadoop/hbase/util/ChecksumType.java