List of comment headers.

List of record fields. It holds all available record fields except comments.

Holds the list of reference sequences name and length. SAMParser update this property from SQ header if present, else this will be updated from the each alignment information in this case length of reference sequence will be unknown thus set to zero. BAMParser update this property from reference information block and not from the SQ header. BAMFormatter uses this information to write reference information block. SAMFormatter does not requires this information, thus ignores this info.