in src/main/java/com/amazon/kinesis/kafka/AmazonKinesisSinkTask.java [330:341]
public void stop() {
// destroying kinesis producers which were not closed as part of close
if (singleKinesisProducerPerPartition) {
for (KinesisProducer kp : producerMap.values()) {
kp.flushSync();
kp.destroy();
}
} else {
kinesisProducer.destroy();
}
}