/**
* If we receive an ACK or RST, we mark the outgoing request or response as acknowledged or
* rejected respectively and cancel its retransmission.
*/
@Override
public void receiveEmptyMessage(Exchange exchange, EmptyMessage message) {
exchange.setFailedTransmissionCount(0);
// TODO: If this is an observe relation, the current response might not
// be the one that is being acknowledged. The current response might
// already be the next NON notification.
if (message.getType() == Type.ACK) {
if (exchange.getOrigin() == Origin.LOCAL) {
exchange.getCurrentRequest().setAcknowledged(true);
} else {
exchange.getCurrentResponse().setAcknowledged(true);
}
} else if (message.getType() == Type.RST) {
if (exchange.getOrigin() == Origin.LOCAL) {
exchange.getCurrentRequest().setRejected(true);
} else {
exchange.getCurrentResponse().setRejected(true);
}
} else {
LOGGER.warning("Empty messgae was not ACK nor RST: " + message);
}
LOGGER.finer("Cancel retransmission");
exchange.setRetransmissionHandle(null);
super.receiveEmptyMessage(exchange, message);
}
@Override
public void run() {
/*
* Do not retransmit a message if it has been acknowledged,
* rejected, canceled or already been retransmitted for the maximum
* number of times.
*/
try {
int failedCount = exchange.getFailedTransmissionCount() + 1;
exchange.setFailedTransmissionCount(failedCount);
if (message.isAcknowledged()) {
LOGGER.finest(
"Timeout: message already acknowledged, cancel retransmission of " + message);
return;
} else if (message.isRejected()) {
LOGGER.finest("Timeout: message already rejected, cancel retransmission of " + message);
return;
} else if (message.isCanceled()) {
LOGGER.finest("Timeout: canceled (MID=" + message.getMID() + "), do not retransmit");
return;
} else if (failedCount <= max_retransmit) {
LOGGER.finer(
"Timeout: retransmit message, failed: " + failedCount + ", message: " + message);
// Trigger MessageObservers
message.retransmitting();
// MessageObserver might have canceled
if (!message.isCanceled()) retransmit();
} else {
LOGGER.info(
"Timeout: retransmission limit reached, exchange failed, message: " + message);
exchange.setTimedOut();
message.setTimedOut(true);
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* When we receive a Confirmable response, we acknowledge it and it also counts as acknowledgment
* for the request. If the response is a duplicate, we stop it here and do not forward it to the
* upper layer.
*/
@Override
public void receiveResponse(Exchange exchange, Response response) {
exchange.setFailedTransmissionCount(0);
exchange.getCurrentRequest().setAcknowledged(true);
LOGGER.finest("Cancel any retransmission");
exchange.setRetransmissionHandle(null);
if (response.getType() == Type.CON && !exchange.getRequest().isCanceled()) {
LOGGER.finer("Response is confirmable, send ACK");
EmptyMessage ack = EmptyMessage.newACK(response);
sendEmptyMessage(exchange, ack);
}
if (response.isDuplicate()) {
LOGGER.fine("Response is duplicate, ignore it");
} else {
super.receiveResponse(exchange, response);
}
}