org.springframework.kafka.core

Class KafkaTemplate<K,V>

java.lang.Object

org.springframework.kafka.core.KafkaTemplate<K,V>

Type Parameters:

K - the key type.

V - the value type.

All Implemented Interfaces:

KafkaOperations<K,V>

public class KafkaTemplate<K,V>
extends java.lang.Object
implements KafkaOperations<K,V>

A template for executing high-level operations.

Author:

Marius Bogoevici, Gary Russell, Igor Stepanov, Artem Bilan

Nested Class Summary

Nested classes/interfaces inherited from interface org.springframework.kafka.core.KafkaOperations

KafkaOperations.ProducerCallback<K,V,T>

Field Summary

Fields

Modifier and Type	Field and Description
protected org.apache.commons.logging.Log	logger

Constructor Summary

Constructors

Constructor and Description
KafkaTemplate(ProducerFactory<K,V> producerFactory) Create an instance using the supplied producer factory and autoFlush false.
KafkaTemplate(ProducerFactory<K,V> producerFactory, boolean autoFlush) Create an instance using the supplied producer factory and autoFlush setting.

Method Summary

Modifier and Type	Method and Description
protected org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	doSend(org.apache.kafka.clients.producer.ProducerRecord<K,V> producerRecord) Send the producer record.
<T> T	execute(KafkaOperations.ProducerCallback<K,V,T> callback) Execute some arbitrary operation(s) on the producer and return the result.
void	flush() Flush the producer.
java.lang.String	getDefaultTopic() The default topic for send methods where a topic is not providing.
MessageConverter	getMessageConverter() Return the message converter.
java.util.Map<org.apache.kafka.common.MetricName,? extends org.apache.kafka.common.Metric>	metrics() See Producer.metrics().
java.util.List<org.apache.kafka.common.PartitionInfo>	partitionsFor(java.lang.String topic) See Producer.partitionsFor(String).
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(org.springframework.messaging.Message<?> message) Send a message with routing information in message headers.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(org.apache.kafka.clients.producer.ProducerRecord<K,V> record)
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(java.lang.String topic, int partition, K key, V data) Send the data to the provided topic with the provided key and partition.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(java.lang.String topic, int partition, V data) Send the data to the provided topic with the provided partition and no key.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(java.lang.String topic, K key, V data) Send the data to the provided topic with the provided key and no partition.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	send(java.lang.String topic, V data) Send the data to the provided topic with no key or partition.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	sendDefault(int partition, K key, V data) Send the data to the default topic with the provided key and partition.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	sendDefault(K key, V data) Send the data to the default topic with the provided key and no partition.
org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>>	sendDefault(V data) Send the data to the default topic with no key or partition.
void	setDefaultTopic(java.lang.String defaultTopic) Set the default topic for send methods where a topic is not providing.
void	setMessageConverter(RecordMessageConverter messageConverter) Set the message converter to use.
void	setProducerListener(ProducerListener<K,V> producerListener) Set a ProducerListener which will be invoked when Kafka acknowledges a send operation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

logger

protected final org.apache.commons.logging.Log logger

Constructor Detail

KafkaTemplate

public KafkaTemplate(ProducerFactory<K,V> producerFactory)

Create an instance using the supplied producer factory and autoFlush false.

Parameters:

producerFactory - the producer factory.

KafkaTemplate

public KafkaTemplate(ProducerFactory<K,V> producerFactory,
                     boolean autoFlush)

Create an instance using the supplied producer factory and autoFlush setting. Set autoFlush to true if you wish to synchronously interact with Kafka, calling Future.get() on the result.

Parameters:

producerFactory - the producer factory.

autoFlush - true to flush after each send.

Method Detail

getDefaultTopic

public java.lang.String getDefaultTopic()

The default topic for send methods where a topic is not providing.

Returns:

the topic.

setDefaultTopic

public void setDefaultTopic(java.lang.String defaultTopic)

Set the default topic for send methods where a topic is not providing.

Parameters:

defaultTopic - the topic.

setProducerListener

public void setProducerListener(ProducerListener<K,V> producerListener)

Set a ProducerListener which will be invoked when Kafka acknowledges a send operation. By default a LoggingProducerListener is configured which logs errors only.

Parameters:

producerListener - the listener; may be null.

getMessageConverter

public MessageConverter getMessageConverter()

Return the message converter.

Returns:

the message converter.

setMessageConverter

public void setMessageConverter(RecordMessageConverter messageConverter)

Set the message converter to use.

Parameters:

messageConverter - the message converter.

sendDefault

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> sendDefault(V data)

Description copied from interface: KafkaOperations

Send the data to the default topic with no key or partition.

Specified by:

sendDefault in interface KafkaOperations<K,V>

Parameters:

data - The data.

Returns:

a Future for the SendResult.

sendDefault

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> sendDefault(K key,
                                                                                         V data)

Description copied from interface: KafkaOperations

Send the data to the default topic with the provided key and no partition.

Specified by:

sendDefault in interface KafkaOperations<K,V>

Parameters:

key - the key.

data - The data.

Returns:

a Future for the SendResult.

sendDefault

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> sendDefault(int partition,
                                                                                         K key,
                                                                                         V data)

Description copied from interface: KafkaOperations

Send the data to the default topic with the provided key and partition.

Specified by:

sendDefault in interface KafkaOperations<K,V>

Parameters:

partition - the partition.

key - the key.

data - the data.

Returns:

a Future for the SendResult.

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(java.lang.String topic,
                                                                                  V data)

Description copied from interface: KafkaOperations

Send the data to the provided topic with no key or partition.

Specified by:

send in interface KafkaOperations<K,V>

Parameters:

topic - the topic.

data - The data.

Returns:

a Future for the SendResult.

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(java.lang.String topic,
                                                                                  K key,
                                                                                  V data)

Description copied from interface: KafkaOperations

Send the data to the provided topic with the provided key and no partition.

Specified by:

send in interface KafkaOperations<K,V>

Parameters:

topic - the topic.

key - the key.

data - The data.

Returns:

a Future for the SendResult.

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(java.lang.String topic,
                                                                                  int partition,
                                                                                  V data)

Description copied from interface: KafkaOperations

Send the data to the provided topic with the provided partition and no key.

Specified by:

send in interface KafkaOperations<K,V>

Parameters:

topic - the topic.

partition - the partition.

data - The data.

Returns:

a Future for the SendResult.

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(java.lang.String topic,
                                                                                  int partition,
                                                                                  K key,
                                                                                  V data)

Description copied from interface: KafkaOperations

Send the data to the provided topic with the provided key and partition.

Specified by:

send in interface KafkaOperations<K,V>

Parameters:

topic - the topic.

partition - the partition.

key - the key.

data - the data.

Returns:

a Future for the SendResult.

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(org.apache.kafka.clients.producer.ProducerRecord<K,V> record)

send

public org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> send(org.springframework.messaging.Message<?> message)

Description copied from interface: KafkaOperations

Send a message with routing information in message headers. The message payload may be converted before sending.

Specified by:

send in interface KafkaOperations<K,V>

Parameters:

message - the message to send.

Returns:

a Future for the SendResult.

See Also:

KafkaHeaders.TOPIC, KafkaHeaders.PARTITION_ID, KafkaHeaders.MESSAGE_KEY

partitionsFor

public java.util.List<org.apache.kafka.common.PartitionInfo> partitionsFor(java.lang.String topic)

Description copied from interface: KafkaOperations

See Producer.partitionsFor(String).

Specified by:

partitionsFor in interface KafkaOperations<K,V>

Parameters:

topic - the topic.

Returns:

the partition info.

metrics

public java.util.Map<org.apache.kafka.common.MetricName,? extends org.apache.kafka.common.Metric> metrics()

Description copied from interface: KafkaOperations

See Producer.metrics().

Specified by:

metrics in interface KafkaOperations<K,V>

Returns:

the metrics.

execute

public <T> T execute(KafkaOperations.ProducerCallback<K,V,T> callback)

Description copied from interface: KafkaOperations

Execute some arbitrary operation(s) on the producer and return the result.

Specified by:

execute in interface KafkaOperations<K,V>

Type Parameters:

T - the result type.

Parameters:

callback - the callback.

Returns:

the result.

flush

public void flush()

Flush the producer.

Note It only makes sense to invoke this method if the ProducerFactory serves up a singleton producer (such as the DefaultKafkaProducerFactory).

Specified by:

flush in interface KafkaOperations<K,V>

doSend

protected org.springframework.util.concurrent.ListenableFuture<SendResult<K,V>> doSend(org.apache.kafka.clients.producer.ProducerRecord<K,V> producerRecord)

Send the producer record.

Parameters:

producerRecord - the producer record.

Returns:

a Future for the RecordMetadata.