abstract fun batchHandler(handler: Handler<ConsumerRecords<K, V>>): KafkaReadStream<K, V>
Set the handler that will be called when a new batch of records is returned from Kafka. Batch handlers need to take care not to block the event loop when dealing with large batches. It is better to process records individually using the record handler.
handler - handler called each time Kafka returns a batch of records.
Return
current KafkaReadStream instance.