private int compare(Revision a, Revision b) {
if (Arrays.equals(a._id, b._id)) return 0;
Version va = getVersion(a);
Version vb = getVersion(b);
int n = va.compareTo(vb);
if (n != 0) return n;
if (a.created != b.created) return a.created > b.created ? 1 : -1;
for (int i = 0; i < a._id.length; i++)
if (a._id[i] != b._id[i]) return a._id[i] > b._id[i] ? 1 : -1;
return 0;
}
/**
* Start up the connection, including the MainLoop thread. Sends the protocol version negotiation
* header, and runs through Connection.Start/.StartOk, Connection.Tune/.TuneOk, and then calls
* Connection.Open and waits for the OpenOk. Sets heart-beat and frame max values after tuning has
* taken place.
*
* @throws IOException if an error is encountered either before, or during, protocol negotiation;
* sub-classes {@link ProtocolVersionMismatchException} and {@link
* PossibleAuthenticationFailureException} will be thrown in the corresponding circumstances.
* {@link AuthenticationFailureException} will be thrown if the broker closes the connection
* with ACCESS_REFUSED. If an exception is thrown, connection resources allocated can all be
* garbage collected when the connection object is no longer referenced.
*/
public void start() throws IOException, TimeoutException {
initializeConsumerWorkService();
initializeHeartbeatSender();
this._running = true;
// Make sure that the first thing we do is to send the header,
// which should cause any socket errors to show up for us, rather
// than risking them pop out in the MainLoop
AMQChannel.SimpleBlockingRpcContinuation connStartBlocker =
new AMQChannel.SimpleBlockingRpcContinuation();
// We enqueue an RPC continuation here without sending an RPC
// request, since the protocol specifies that after sending
// the version negotiation header, the client (connection
// initiator) is to wait for a connection.start method to
// arrive.
_channel0.enqueueRpc(connStartBlocker);
try {
// The following two lines are akin to AMQChannel's
// transmit() method for this pseudo-RPC.
_frameHandler.setTimeout(handshakeTimeout);
_frameHandler.sendHeader();
} catch (IOException ioe) {
_frameHandler.close();
throw ioe;
}
// start the main loop going
MainLoop loop = new MainLoop();
final String name = "AMQP Connection " + getHostAddress() + ":" + getPort();
mainLoopThread = Environment.newThread(threadFactory, loop, name);
mainLoopThread.start();
// after this point clear-up of MainLoop is triggered by closing the frameHandler.
AMQP.Connection.Start connStart;
AMQP.Connection.Tune connTune = null;
try {
connStart =
(AMQP.Connection.Start) connStartBlocker.getReply(handshakeTimeout / 2).getMethod();
_serverProperties = Collections.unmodifiableMap(connStart.getServerProperties());
Version serverVersion = new Version(connStart.getVersionMajor(), connStart.getVersionMinor());
if (!Version.checkVersion(clientVersion, serverVersion)) {
throw new ProtocolVersionMismatchException(clientVersion, serverVersion);
}
String[] mechanisms = connStart.getMechanisms().toString().split(" ");
SaslMechanism sm = this.saslConfig.getSaslMechanism(mechanisms);
if (sm == null) {
throw new IOException(
"No compatible authentication mechanism found - "
+ "server offered ["
+ connStart.getMechanisms()
+ "]");
}
LongString challenge = null;
LongString response = sm.handleChallenge(null, this.username, this.password);
do {
Method method =
(challenge == null)
? new AMQP.Connection.StartOk.Builder()
.clientProperties(_clientProperties)
.mechanism(sm.getName())
.response(response)
.build()
: new AMQP.Connection.SecureOk.Builder().response(response).build();
try {
Method serverResponse = _channel0.rpc(method, handshakeTimeout / 2).getMethod();
if (serverResponse instanceof AMQP.Connection.Tune) {
connTune = (AMQP.Connection.Tune) serverResponse;
} else {
challenge = ((AMQP.Connection.Secure) serverResponse).getChallenge();
response = sm.handleChallenge(challenge, this.username, this.password);
}
} catch (ShutdownSignalException e) {
Method shutdownMethod = e.getReason();
if (shutdownMethod instanceof AMQP.Connection.Close) {
AMQP.Connection.Close shutdownClose = (AMQP.Connection.Close) shutdownMethod;
if (shutdownClose.getReplyCode() == AMQP.ACCESS_REFUSED) {
throw new AuthenticationFailureException(shutdownClose.getReplyText());
}
}
throw new PossibleAuthenticationFailureException(e);
}
} while (connTune == null);
} catch (TimeoutException te) {
_frameHandler.close();
throw te;
} catch (ShutdownSignalException sse) {
_frameHandler.close();
throw AMQChannel.wrap(sse);
} catch (IOException ioe) {
_frameHandler.close();
throw ioe;
}
try {
int channelMax = negotiateChannelMax(this.requestedChannelMax, connTune.getChannelMax());
_channelManager = instantiateChannelManager(channelMax, threadFactory);
int frameMax = negotiatedMaxValue(this.requestedFrameMax, connTune.getFrameMax());
this._frameMax = frameMax;
int heartbeat = negotiatedMaxValue(this.requestedHeartbeat, connTune.getHeartbeat());
setHeartbeat(heartbeat);
_channel0.transmit(
new AMQP.Connection.TuneOk.Builder()
.channelMax(channelMax)
.frameMax(frameMax)
.heartbeat(heartbeat)
.build());
_channel0.exnWrappingRpc(
new AMQP.Connection.Open.Builder().virtualHost(_virtualHost).build());
} catch (IOException ioe) {
_heartbeatSender.shutdown();
_frameHandler.close();
throw ioe;
} catch (ShutdownSignalException sse) {
_heartbeatSender.shutdown();
_frameHandler.close();
throw AMQChannel.wrap(sse);
}
// We can now respond to errors having finished tailoring the connection
this._inConnectionNegotiation = false;
}