public void
setTSIG(TSIG key, int error, TSIGRecord querytsig) {
	this.tsigkey = key;
	this.tsigerror = error;
	this.querytsig = querytsig;
}
Sets the TSIG key and other necessary information to sign a message.
@param key The TSIG key.
@param error The value of the TSIG error field.
@param querytsig If this is a response, the TSIG from the request.
src/main/java/core/org/xbill/DNS/Message.java