org.springframework.kafka.listener.adapter

Class MessagingMessageListenerAdapter<K,V>

java.lang.Object

org.springframework.kafka.listener.adapter.MessagingMessageListenerAdapter<K,V>

Type Parameters:

K - the key type.

V - the value type.

All Implemented Interfaces:

ConsumerSeekAware

Direct Known Subclasses:

BatchMessagingMessageListenerAdapter, RecordMessagingMessageListenerAdapter

public abstract class MessagingMessageListenerAdapter<K,V>
extends java.lang.Object
implements ConsumerSeekAware

An abstract MessageListener adapter providing the necessary infrastructure to extract the payload of a Message.

Author:

Stephane Nicoll, Gary Russell, Artem Bilan

Nested Class Summary

Nested classes/interfaces inherited from interface org.springframework.kafka.listener.ConsumerSeekAware

ConsumerSeekAware.ConsumerSeekCallback

Field Summary

Fields

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

Constructor Summary

Constructors

Constructor and Description
MessagingMessageListenerAdapter(java.lang.Object bean, java.lang.reflect.Method method)

Method Summary

Modifier and Type	Method and Description
protected java.lang.reflect.Type	determineInferredType(java.lang.reflect.Method method) Subclasses can override this method to use a different mechanism to determine the target type of the payload conversion.
protected RecordMessageConverter	getMessageConverter() Return the MessagingMessageConverter for this listener, being able to convert Message.
protected java.lang.reflect.Type	getType() Returns the inferred type for conversion or, if null, the fallbackType.
protected java.lang.Object	invokeHandler(java.lang.Object data, Acknowledgment acknowledgment, org.springframework.messaging.Message<?> message) Invoke the handler, wrapping any exception to a ListenerExecutionFailedException with a dedicated error message.
protected boolean	isConsumerRecordList()
protected boolean	isMessageList()
void	onIdleContainer(java.util.Map<org.apache.kafka.common.TopicPartition,java.lang.Long> assignments, ConsumerSeekAware.ConsumerSeekCallback callback) If the container is configured to emit idle container events, this method is called when the container idle event is emitted - allowing a seek operation.
void	onPartitionsAssigned(java.util.Map<org.apache.kafka.common.TopicPartition,java.lang.Long> assignments, ConsumerSeekAware.ConsumerSeekCallback callback) When using group management, called when partition assignments change.
void	registerSeekCallback(ConsumerSeekAware.ConsumerSeekCallback callback) Register the callback to use when seeking at some arbitrary time.
void	setFallbackType(java.lang.Class<?> fallbackType) Set a fallback type to use when using a type-aware message converter and this adapter cannot determine the inferred type from the method.
void	setHandlerMethod(HandlerAdapter handlerMethod) Set the HandlerAdapter to use to invoke the method processing an incoming ConsumerRecord.
void	setMessageConverter(RecordMessageConverter messageConverter) Set the MessageConverter.
protected org.springframework.messaging.Message<?>	toMessagingMessage(org.apache.kafka.clients.consumer.ConsumerRecord<K,V> record, Acknowledgment acknowledgment)

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

MessagingMessageListenerAdapter

public MessagingMessageListenerAdapter(java.lang.Object bean,
                                       java.lang.reflect.Method method)

Method Detail

setMessageConverter

public void setMessageConverter(RecordMessageConverter messageConverter)

Set the MessageConverter.

Parameters:

messageConverter - the converter.

getMessageConverter

protected final RecordMessageConverter getMessageConverter()

Return the MessagingMessageConverter for this listener, being able to convert Message.

Returns:

the MessagingMessageConverter for this listener, being able to convert Message.

getType

protected java.lang.reflect.Type getType()

Returns the inferred type for conversion or, if null, the fallbackType.

Returns:

the type.

setFallbackType

public void setFallbackType(java.lang.Class<?> fallbackType)

Set a fallback type to use when using a type-aware message converter and this adapter cannot determine the inferred type from the method. An example of a type-aware message converter is the StringJsonMessageConverter. Defaults to Object.

Parameters:

fallbackType - the type.

setHandlerMethod

public void setHandlerMethod(HandlerAdapter handlerMethod)

Set the HandlerAdapter to use to invoke the method processing an incoming ConsumerRecord.

Parameters:

handlerMethod - HandlerAdapter instance.

isConsumerRecordList

protected boolean isConsumerRecordList()

isMessageList

protected boolean isMessageList()

registerSeekCallback

public void registerSeekCallback(ConsumerSeekAware.ConsumerSeekCallback callback)

Description copied from interface: ConsumerSeekAware

Register the callback to use when seeking at some arbitrary time. When used with a ConcurrentMessageListenerContainer or the same listener instance in multiple containers listeners should store the callback in a ThreadLocal.

Specified by:

registerSeekCallback in interface ConsumerSeekAware

Parameters:

callback - the callback.

onPartitionsAssigned

public void onPartitionsAssigned(java.util.Map<org.apache.kafka.common.TopicPartition,java.lang.Long> assignments,
                                 ConsumerSeekAware.ConsumerSeekCallback callback)

Description copied from interface: ConsumerSeekAware

When using group management, called when partition assignments change.

Specified by:

onPartitionsAssigned in interface ConsumerSeekAware

Parameters:

assignments - the new assignments and their current offsets.

callback - the callback to perform an initial seek after assignment.

onIdleContainer

public void onIdleContainer(java.util.Map<org.apache.kafka.common.TopicPartition,java.lang.Long> assignments,
                            ConsumerSeekAware.ConsumerSeekCallback callback)

Description copied from interface: ConsumerSeekAware

If the container is configured to emit idle container events, this method is called when the container idle event is emitted - allowing a seek operation.

Specified by:

onIdleContainer in interface ConsumerSeekAware

Parameters:

assignments - the new assignments and their current offsets.

callback - the callback to perform a seek.

toMessagingMessage

protected org.springframework.messaging.Message<?> toMessagingMessage(org.apache.kafka.clients.consumer.ConsumerRecord<K,V> record,
                                                                      Acknowledgment acknowledgment)

invokeHandler

protected final java.lang.Object invokeHandler(java.lang.Object data,
                                               Acknowledgment acknowledgment,
                                               org.springframework.messaging.Message<?> message)

Invoke the handler, wrapping any exception to a ListenerExecutionFailedException with a dedicated error message.

Parameters:

data - the data to process during invocation.

acknowledgment - the acknowledgment to use if any.

message - the message to process.

Returns:

the result of invocation.

determineInferredType

protected java.lang.reflect.Type determineInferredType(java.lang.reflect.Method method)

Subclasses can override this method to use a different mechanism to determine the target type of the payload conversion.

Parameters:

method - the method.

Returns:

the type.