/**
* Build the announce request tracker message.
*
* @param event The announce event (can be <tt>NONE</tt> or <em>null</em>)
* @return Returns an instance of a {@link HTTPAnnounceRequestMessage} that can be used to
* generate the fully qualified announce URL, with parameters, to make the announce request.
* @throws UnsupportedEncodingException
* @throws IOException
* @throws MessageValidationException
*/
private HTTPAnnounceRequestMessage buildAnnounceRequest(AnnounceRequestMessage.RequestEvent event)
throws UnsupportedEncodingException, IOException, MessageValidationException {
// Build announce request message
return HTTPAnnounceRequestMessage.craft(
this.torrent.getInfoHash(),
this.peer.getPeerId().array(),
this.peer.getPort(),
this.torrent.getUploaded(),
this.torrent.getDownloaded(),
this.torrent.getLeft(),
true,
false,
event,
this.peer.getIp(),
AnnounceRequestMessage.DEFAULT_NUM_WANT);
}
/**
* Build, send and process a tracker announce request.
*
* <p>This function first builds an announce request for the specified event with all the required
* parameters. Then, the request is made to the tracker and the response analyzed.
*
* <p>All registered {@link AnnounceResponseListener} objects are then fired with the decoded
* payload.
*
* @param event The announce event type (can be AnnounceEvent.NONE for periodic updates).
* @param inhibitEvents Prevent event listeners from being notified.
*/
@Override
public void announce(AnnounceRequestMessage.RequestEvent event, boolean inhibitEvents)
throws AnnounceException {
logger.info(
"Announcing{} to tracker with {}U/{}D/{}L bytes...",
new Object[] {
this.formatAnnounceEvent(event),
this.torrent.getUploaded(),
this.torrent.getDownloaded(),
this.torrent.getLeft()
});
URL target = null;
try {
HTTPAnnounceRequestMessage request = this.buildAnnounceRequest(event);
target = request.buildAnnounceURL(this.tracker.toURL());
} catch (MalformedURLException mue) {
throw new AnnounceException("Invalid announce URL (" + mue.getMessage() + ")", mue);
} catch (MessageValidationException mve) {
throw new AnnounceException(
"Announce request creation violated " + "expected protocol (" + mve.getMessage() + ")",
mve);
} catch (IOException ioe) {
throw new AnnounceException(
"Error building announce request (" + ioe.getMessage() + ")", ioe);
}
HttpURLConnection conn = null;
InputStream in = null;
try {
conn = (HttpURLConnection) target.openConnection();
in = conn.getInputStream();
} catch (IOException ioe) {
if (conn != null) {
in = conn.getErrorStream();
}
}
// At this point if the input stream is null it means we have neither a
// response body nor an error stream from the server. No point in going
// any further.
if (in == null) {
throw new AnnounceException("No response or unreachable tracker!");
}
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
baos.write(in);
// Parse and handle the response
HTTPTrackerMessage message = HTTPTrackerMessage.parse(ByteBuffer.wrap(baos.toByteArray()));
baos.close(); // close stream
this.handleTrackerAnnounceResponse(message, inhibitEvents);
} catch (IOException ioe) {
throw new AnnounceException("Error reading tracker response!", ioe);
} catch (MessageValidationException mve) {
throw new AnnounceException(
"Tracker message violates expected " + "protocol (" + mve.getMessage() + ")", mve);
} finally {
// Make sure we close everything down at the end to avoid resource
// leaks.
try {
in.close();
} catch (IOException ioe) {
logger.warn("Problem ensuring error stream closed!", ioe);
}
// This means trying to close the error stream as well.
InputStream err = conn.getErrorStream();
if (err != null) {
try {
err.close();
} catch (IOException ioe) {
logger.warn("Problem ensuring error stream closed!", ioe);
}
}
}
}
