/**
* Builds a new Record from its textual representation
*
* @param name The owner name of the record.
* @param type The record's type.
* @param dclass The record's class.
* @param ttl The record's time to live.
* @param st A tokenizer containing the textual representation of the rdata.
* @param origin The default origin to be appended to relative domain names.
* @return The new record
* @throws IOException The text format was invalid.
*/
public static Record fromString(
Name name, int type, int dclass, long ttl, Tokenizer st, Name origin) throws IOException {
Record rec;
if (!name.isAbsolute()) throw new RelativeNameException(name);
Type.check(type);
DClass.check(dclass);
TTL.check(ttl);
Tokenizer.Token t = st.get();
if (t.type == Tokenizer.IDENTIFIER && t.value.equals("\\#")) {
int length = st.getUInt16();
byte[] data = st.getHex();
if (data == null) {
data = new byte[0];
}
if (length != data.length)
throw st.exception("invalid unknown RR encoding: " + "length mismatch");
DNSInput in = new DNSInput(data);
return newRecord(name, type, dclass, ttl, length, in);
}
st.unget();
rec = getEmptyRecord(name, type, dclass, ttl, true);
rec.rdataFromString(st, origin);
t = st.get();
if (t.type != Tokenizer.EOL && t.type != Tokenizer.EOF) {
throw st.exception("unexpected tokens at end of record");
}
return rec;
}
/**
* Creates a new empty record, with the given parameters.
*
* @param name The owner name of the record.
* @param type The record's type.
* @param dclass The record's class.
* @param ttl The record's time to live.
* @return An object of a subclass of Record
*/
public static Record newRecord(Name name, int type, int dclass, long ttl) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
Type.check(type);
DClass.check(dclass);
TTL.check(ttl);
return getEmptyRecord(name, type, dclass, ttl, false);
}
Record(Name name, int type, int dclass, long ttl) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
Type.check(type);
DClass.check(dclass);
TTL.check(ttl);
this.name = name;
this.type = type;
this.dclass = dclass;
this.ttl = ttl;
}
/**
* Creates a new record, with the given parameters.
*
* @param name The owner name of the record.
* @param type The record's type.
* @param dclass The record's class.
* @param ttl The record's time to live.
* @param length The length of the record's data.
* @param data The rdata of the record, in uncompressed DNS wire format. Only the first length
* bytes are used.
*/
public static Record newRecord(
Name name, int type, int dclass, long ttl, int length, byte[] data) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
Type.check(type);
DClass.check(dclass);
TTL.check(ttl);
DNSInput in;
if (data != null) in = new DNSInput(data);
else in = null;
try {
return newRecord(name, type, dclass, ttl, length, in);
} catch (IOException e) {
return null;
}
}
/* Checks that a name is absolute */
static Name checkName(String field, Name name) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
return name;
}
/**
* Creates a new record identical to the current record, but with a different name. This is most
* useful for replacing the name of a wildcard record.
*/
public Record withName(Name name) {
if (!name.isAbsolute()) throw new RelativeNameException(name);
Record rec = cloneRecord();
rec.name = name;
return rec;
}