in flink-connector-rabbitmq/src/main/java/org/apache/flink/streaming/connectors/rabbitmq/RMQSource.java [314:320]
private void processMessage(Delivery delivery, RMQCollectorImpl collector) throws IOException {
AMQP.BasicProperties properties = delivery.getProperties();
byte[] body = delivery.getBody();
Envelope envelope = delivery.getEnvelope();
collector.setFallBackIdentifiers(properties.getCorrelationId(), envelope.getDeliveryTag());
deliveryDeserializer.deserialize(envelope, properties, body, collector);
}