/**
* Computes the back-off timer and schedules the specified retransmission task.
*
* @param exchange the exchange
* @param task the retransmission task
*/
protected void prepareRetransmission(Exchange exchange, RetransmissionTask task) {
/*
* For a new confirmable message, the initial timeout is set to a
* random number between ACK_TIMEOUT and (ACK_TIMEOUT *
* ACK_RANDOM_FACTOR)
*/
int timeout;
if (exchange.getFailedTransmissionCount() == 0) {
timeout = getRandomTimeout(ack_timeout, (int) (ack_timeout * ack_random_factor));
} else {
timeout = (int) (ack_timeout_scale * exchange.getCurrentTimeout());
}
exchange.setCurrentTimeout(timeout);
ScheduledFuture<?> f = executor.schedule(task, timeout, TimeUnit.MILLISECONDS);
exchange.setRetransmissionHandle(f);
}
