public List
run() throws IOException, ZoneTransferException {
	BasicHandler handler = new BasicHandler();
	run(handler);
	if (handler.axfr != null)
		return handler.axfr;
	return handler.ixfr;
}
Does the zone transfer.
@return A list, which is either an AXFR-style response (List of Records),
and IXFR-style response (List of Deltas), or null, which indicates that
an IXFR was performed and the zone is up to date.
@throws IOException The zone transfer failed to due an IO problem.
@throws ZoneTransferException The zone transfer failed to due a problem
with the zone transfer itself.
src/main/java/core/org/xbill/DNS/ZoneTransferIn.java