Package org.apache.kafka.clients.producer

Class ProducerRecord<K,V>

java.lang.Object
org.apache.kafka.clients.producer.ProducerRecord<K,V>
public class ProducerRecord<K,V> extends Object
A key/value pair to be sent to Kafka. This consists of a topic name to which the record is being sent, an optional partition number, and an optional key and value.

If a valid partition number is specified that partition will be used when sending the record. If no partition is specified but a key is present a partition will be chosen using a hash of the key. If neither key nor partition is present a partition will be assigned in a round-robin fashion. Note that partition numbers are 0-indexed.

The record also has an associated timestamp. If the user did not provide a timestamp, the producer will stamp the record with its current time. The timestamp eventually used by Kafka depends on the timestamp type configured for the topic.

  • If the topic is configured to use CreateTime, the timestamp in the producer record will be used by the broker.
  • If the topic is configured to use LogAppendTime, the timestamp in the producer record will be overwritten by the broker with the broker local time when it appends the message to its log.

    • In either of the cases above, the timestamp that has actually been used will be returned to user in RecordMetadata

    • Constructor Details

      • ProducerRecord

        public ProducerRecord(String topic, Integer partition, Long timestamp, K key, V value, Iterable<Header> headers)
        Creates a record with a specified timestamp to be sent to a specified topic and partition
        Parameters:
        topic - The topic the record will be appended to
        partition - The partition to which the record should be sent
        timestamp - The timestamp of the record, in milliseconds since epoch. If null, the producer will assign the timestamp using System.currentTimeMillis().
        key - The key that will be included in the record
        value - The record contents
        headers - the headers that will be included in the record

      • ProducerRecord

        public ProducerRecord(String topic, Integer partition, Long timestamp, K key, V value)
        Creates a record with a specified timestamp to be sent to a specified topic and partition
        Parameters:
        topic - The topic the record will be appended to
        partition - The partition to which the record should be sent
        timestamp - The timestamp of the record, in milliseconds since epoch. If null, the producer will assign the timestamp using System.currentTimeMillis().
        key - The key that will be included in the record
        value - The record contents

      • ProducerRecord

        public ProducerRecord(String topic, Integer partition, K key, V value, Iterable<Header> headers)
        Creates a record to be sent to a specified topic and partition
        Parameters:
        topic - The topic the record will be appended to
        partition - The partition to which the record should be sent
        key - The key that will be included in the record
        value - The record contents
        headers - The headers that will be included in the record

      • ProducerRecord

        public ProducerRecord(String topic, Integer partition, K key, V value)
        Creates a record to be sent to a specified topic and partition
        Parameters:
        topic - The topic the record will be appended to
        partition - The partition to which the record should be sent
        key - The key that will be included in the record
        value - The record contents

      • ProducerRecord

        public ProducerRecord(String topic, K key, V value)
        Create a record to be sent to Kafka
        Parameters:
        topic - The topic the record will be appended to
        key - The key that will be included in the record
        value - The record contents

      • ProducerRecord

        public ProducerRecord(String topic, V value)
        Create a record with no key
        Parameters:
        topic - The topic this record should be sent to
        value - The record contents

    • Method Details

      • topic

        public String topic()
        Returns:
        The topic this record is being sent to

      • headers

        public Headers headers()
        Returns:
        The headers

      • key

        public K key()
        Returns:
        The key (or null if no key is specified)

      • value

        public V value()
        Returns:
        The value

      • timestamp

        public Long timestamp()
        Returns:
        The timestamp, which is in milliseconds since epoch.

      • partition

        public Integer partition()
        Returns:
        The partition to which the record will be sent (or null if no partition was specified)

      • toString

        public String toString()
        Overrides:
        toString in class Object

      • equals

        public boolean equals(Object o)
        Overrides:
        equals in class Object

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class Object