/**
* Connects this CDDB instance to the CDDB server running on the supplied host using the specified
* port.
*
* <p><b>Note well:</b> you must close a CDDB connection once you are done with it, otherwise the
* socket connection will remain open and pointlessly consume machine resources.
*
* @param hostname The host to which to connect.
* @param port The port number on which to connect to the host.
* @exception IOException Thrown if a network error occurs attempting to connect to the host.
* @exception CDDBException Thrown if an error occurs after identifying ourselves to the host.
* @return The message supplied with the succesful connection response.
* @see #close
*/
public String connect(String hostname, int port) throws IOException, CDDBException {
// obtain the necessary information we'll need to identify
// ourselves to the CDDB server
String localhost = InetAddress.getLocalHost().getHostName();
String username = System.getProperty("user.name");
if (username == null) {
username = "******";
}
// establish our socket connection and IO streams
InetAddress addr = InetAddress.getByName(hostname);
_sock = new Socket(addr, port);
_in = new BufferedReader(new InputStreamReader(_sock.getInputStream()));
_out = new PrintStream(new BufferedOutputStream(_sock.getOutputStream()));
// first read (and discard) the banner string
_in.readLine();
// send a hello request
StringBuilder req = new StringBuilder("cddb hello ");
req.append(username).append(" ");
req.append(localhost).append(" ");
req.append(CLIENT_NAME).append(" ");
req.append(CLIENT_VERSION);
Response rsp = request(req.toString());
// confirm that the response was a successful one
if (CDDBProtocol.codeFamily(rsp.code) != CDDBProtocol.OK
&& rsp.code != 402 /* already shook hands */) {
throw new CDDBException(rsp.code, rsp.message);
}
return rsp.message;
}
/**
* Issues a query to the CDDB server using the supplied CD identifying information.
*
* @param discid The disc identifier (information on how to compute the disc ID is available <a
* href="http://www.freedb.org/sections.php?op=viewarticle&artid=6">here</a>.
* @param frameOffsets The frame offset of each track. The length of this array is assumed to be
* the number of tracks on the CD and is used in the query.
* @param length The length (in seconds) of the CD.
* @return If no entry matches the query, null is returned. Otherwise one or more entries is
* returned that matched the query parameters.
*/
public Entry[] query(String discid, int[] frameOffsets, int length)
throws IOException, CDDBException {
// sanity check
if (_sock == null) {
throw new CDDBException(500, "Not connected");
}
// construct the query parameter
StringBuilder req = new StringBuilder("cddb query ");
req.append(discid).append(" ");
req.append(frameOffsets.length).append(" ");
for (int frameOffset : frameOffsets) {
req.append(frameOffset).append(" ");
}
req.append(length);
// make the request
Response rsp = request(req.toString());
Entry[] entries = null;
// if this is an exact match, parse the entry and return it
if (rsp.code == 200 /* exact match */) {
entries = new Entry[1];
entries[0] = new Entry();
entries[0].parse(rsp.message);
} else if (rsp.code == 211 /* inexact matches */) {
// read the matches from the server
ArrayList<Entry> list = new ArrayList<Entry>();
String input = _in.readLine();
while (input != null && !input.equals(CDDBProtocol.TERMINATOR)) {
System.out.println("...: " + input);
Entry e = new Entry();
e.parse(input);
list.add(e);
input = _in.readLine();
}
entries = new Entry[list.size()];
list.toArray(entries);
} else if (CDDBProtocol.codeFamily(rsp.code) != CDDBProtocol.OK) {
throw new CDDBException(rsp.code, rsp.message);
}
return entries;
}