public int partitionCount() {
        return partitionCount;
    }
Send a record asynchronously to the configured {@link #topic}.
@param key the key for the {@link ProducerRecord}
@param value the value for the {@link ProducerRecord}
@param callback the callback to invoke after completion; can be null if no callback is desired

@return the future from the call to {@link Producer#send}. {@link Future#get} can be called on this returned
        future if synchronous behavior is desired.
connect/runtime/src/main/java/org/apache/kafka/connect/util/KafkaBasedLog.java