/**
* Creates a new Extended Resolver
*
* @param servers An array of server names for which SimpleResolver contexts should be
* initialized.
* @see SimpleResolver
* @exception UnknownHostException Failure occured initializing SimpleResolvers
*/
public ExtendedResolver(String[] servers) throws UnknownHostException {
init();
for (int i = 0; i < servers.length; i++) {
Resolver r = new SimpleResolver(servers[i]);
r.setTimeout(quantum);
resolvers.add(r);
}
}
/**
* Creates a new Extended Resolver. The default ResolverConfig is used to determine the servers
* for which SimpleResolver contexts should be initialized.
*
* @see SimpleResolver
* @see ResolverConfig
* @exception UnknownHostException Failure occured initializing SimpleResolvers
*/
public ExtendedResolver() throws UnknownHostException {
init();
String[] servers = ResolverConfig.getCurrentConfig().servers();
if (servers != null) {
for (int i = 0; i < servers.length; i++) {
Resolver r = new SimpleResolver(servers[i]);
r.setTimeout(quantum);
resolvers.add(r);
}
} else resolvers.add(new SimpleResolver());
}
public static Record[] getRecords(String namestr, short type, short dclass, byte cred) {
Message query;
Message response;
Record question;
Record[] answers;
int answerCount = 0, i = 0;
Enumeration e;
Name name = new Name(namestr);
/*System.out.println("lookup of " + name + " " + Type.string(type));*/
if (!Type.isRR(type) && type != Type.ANY) return null;
if (res == null) {
try {
eres = new ExtendedResolver();
} catch (UnknownHostException uhe) {
System.out.println("Failed to initialize resolver");
System.exit(-1);
}
}
if (cache == null) cache = new Cache();
CacheResponse cached = cache.lookupRecords(name, type, dclass, cred);
/*System.out.println(cached);*/
if (cached.isSuccessful()) {
RRset rrset = cached.answer();
answerCount = rrset.size();
e = rrset.rrs();
} else if (cached.isNegative()) {
answerCount = 0;
e = null;
} else {
question = Record.newRecord(name, type, dclass);
query = Message.newQuery(question);
if (res != null) response = res.send(query);
else response = eres.send(query);
short rcode = response.getHeader().getRcode();
if (rcode == Rcode.NOERROR || rcode == Rcode.NXDOMAIN) cache.addMessage(response);
if (rcode != Rcode.NOERROR) return null;
e = response.getSection(Section.ANSWER);
while (e.hasMoreElements()) {
Record r = (Record) e.nextElement();
if (matchType(r.getType(), type)) answerCount++;
}
e = response.getSection(Section.ANSWER);
}
if (answerCount == 0) return null;
answers = new Record[answerCount];
while (e.hasMoreElements()) {
Record r = (Record) e.nextElement();
if (matchType(r.getType(), type)) answers[i++] = r;
}
return answers;
}