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, Venil Noronha

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class MessagingMessageListenerAdapter.ReplyExpressionRoot
Root object for reply expression evaluation.
- Nested classes/interfaces inherited from interface org.springframework.kafka.listener.ConsumerSeekAware
  ConsumerSeekAware.ConsumerSeekCallback

Field Summary

Fields
Modifier and Type	Field	Description
`protected org.springframework.core.log.LogAccessor`	`logger`
`protected static org.springframework.messaging.Message<KafkaNull>`	`NULL_MESSAGE`	Message used when no conversion is needed.

Constructor Summary

Constructors
Constructor Description

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

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected java.lang.String`	`createMessagingErrorMessage(java.lang.String description, java.lang.Object payload)`
`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 ReplyHeadersConfigurer`	`getReplyHeadersConfigurer()`	Return the reply configurer.
`protected java.lang.reflect.Type`	`getType()`	Returns the inferred type for conversion or, if null, the `fallbackType`.
`protected void`	`handleResult(java.lang.Object resultArg, java.lang.Object request, java.lang.Object source)`	Handle the given result object returned from the listener method, sending a response message to the SendTo topic.
`protected java.lang.Object`	`invokeHandler(java.lang.Object data, Acknowledgment acknowledgment, org.springframework.messaging.Message<?> message, org.apache.kafka.clients.consumer.Consumer<?,?> consumer)`	Invoke the handler, wrapping any exception to a `ListenerExecutionFailedException` with a dedicated error message.
`protected boolean`	`isConsumerRecordList()`
`boolean`	`isConsumerRecords()`
`boolean`	`isConversionNeeded()`
`protected boolean`	`isMessageList()`
`protected boolean`	`isSplitIterables()`	When true, `Iterable` return results will be split into discrete records.
`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`	`onPartitionsRevoked(java.util.Collection<org.apache.kafka.common.TopicPartition> partitions)`	When using group management, called when partition assignments are revoked.
`void`	`registerSeekCallback(ConsumerSeekAware.ConsumerSeekCallback callback)`	Register the callback to use when seeking at some arbitrary time.
`protected void`	`sendResponse(java.lang.Object result, java.lang.String topic, java.lang.Object source, boolean returnTypeMessage)`	Send the result to the topic.
`void`	`setBeanResolver(org.springframework.expression.BeanResolver beanResolver)`	Set a bean resolver for runtime SpEL expressions.
`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.
`void`	`setReplyHeadersConfigurer(ReplyHeadersConfigurer replyHeadersConfigurer)`	Set a configurer which will be invoked when creating a reply message.
`void`	`setReplyTemplate(KafkaTemplate<?,?> replyTemplate)`	Set the template to use to send any result from the method invocation.
`void`	`setReplyTopic(java.lang.String replyTopicParam)`	Set the topic to which to send any result from the method invocation.
`void`	`setSplitIterables(boolean splitIterables)`	Set to false to disable splitting `Iterable` reply values into separate records.
`protected org.springframework.messaging.Message<?>`	`toMessagingMessage(org.apache.kafka.clients.consumer.ConsumerRecord<K,V> record, Acknowledgment acknowledgment, org.apache.kafka.clients.consumer.Consumer<?,?> consumer)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.springframework.kafka.listener.ConsumerSeekAware
unregisterSeekCallback

- Field Detail
  - NULL_MESSAGE
```
protected static final org.springframework.messaging.Message<KafkaNull> NULL_MESSAGE
```
    Message used when no conversion is needed.
  - logger
```
protected final org.springframework.core.log.LogAccessor 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()
```
  - isConsumerRecords
```
public boolean isConsumerRecords()
```
  - isConversionNeeded
```
public boolean isConversionNeeded()
```
  - setReplyTopic
```
public void setReplyTopic(java.lang.String replyTopicParam)
```
    Set the topic to which to send any result from the method invocation. May be a SpEL expression !{...} evaluated at runtime.
    
    Parameters:
    
    replyTopicParam - the topic or expression.
    
    Since:
    
    2.0
  - setReplyTemplate
```
public void setReplyTemplate(KafkaTemplate<?,?> replyTemplate)
```
    Set the template to use to send any result from the method invocation.
    
    Parameters:
    
    replyTemplate - the template.
    
    Since:
    
    2.0
  - setBeanResolver
```
public void setBeanResolver(org.springframework.expression.BeanResolver beanResolver)
```
    Set a bean resolver for runtime SpEL expressions. Also configures the evaluation context with a standard type converter and map accessor.
    
    Parameters:
    
    beanResolver - the resolver.
    
    Since:
    
    2.0
  - isMessageList
```
protected boolean isMessageList()
```
  - getReplyHeadersConfigurer
```
protected ReplyHeadersConfigurer getReplyHeadersConfigurer()
```
    Return the reply configurer.
    
    Returns:
    
    the configurer.
    
    Since:
    
    2.2
    
    See Also:
    
    setReplyHeadersConfigurer(ReplyHeadersConfigurer)
  - setReplyHeadersConfigurer
```
public void setReplyHeadersConfigurer(ReplyHeadersConfigurer replyHeadersConfigurer)
```
    Set a configurer which will be invoked when creating a reply message.
    
    Parameters:
    
    replyHeadersConfigurer - the configurer.
    
    Since:
    
    2.2
  - isSplitIterables
```
protected boolean isSplitIterables()
```
    When true, Iterable return results will be split into discrete records.
    
    Returns:
    
    true to split.
    
    Since:
    
    2.3.5
  - setSplitIterables
```
public void setSplitIterables(boolean splitIterables)
```
    Set to false to disable splitting Iterable reply values into separate records.
    
    Parameters:
    
    splitIterables - false to disable; default true.
    
    Since:
    
    2.3.5
  - 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.
  - onPartitionsRevoked
```
public void onPartitionsRevoked(java.util.Collection<org.apache.kafka.common.TopicPartition> partitions)
```
    Description copied from interface: ConsumerSeekAware
    
    When using group management, called when partition assignments are revoked. Listeners should discard any callback saved from ConsumerSeekAware.registerSeekCallback(ConsumerSeekCallback) on this thread.
    
    Specified by:
    
    onPartitionsRevoked in interface ConsumerSeekAware
    
    Parameters:
    
    partitions - the partitions that have been revoked.
  - 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,
                                                                      org.apache.kafka.clients.consumer.Consumer<?,?> consumer)
```
  - invokeHandler
```
protected final java.lang.Object invokeHandler(java.lang.Object data,
                                               Acknowledgment acknowledgment,
                                               org.springframework.messaging.Message<?> message,
                                               org.apache.kafka.clients.consumer.Consumer<?,?> consumer)
```
    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.
    
    consumer - the consumer.
    
    Returns:
    
    the result of invocation.
  - handleResult
```
protected void handleResult(java.lang.Object resultArg,
                            java.lang.Object request,
                            java.lang.Object source)
```
    Handle the given result object returned from the listener method, sending a response message to the SendTo topic.
    
    Parameters:
    
    resultArg - the result object to handle (never null)
    
    request - the original request message
    
    source - the source data for the method invocation - e.g. o.s.messaging.Message<?>; may be null
  - sendResponse
```
protected void sendResponse(java.lang.Object result,
                            java.lang.String topic,
                            @Nullable
                            java.lang.Object source,
                            boolean returnTypeMessage)
```
    Send the result to the topic.
    
    Parameters:
    
    result - the result.
    
    topic - the topic.
    
    source - the source (input).
    
    returnTypeMessage - true if we are returning message(s).
    
    Since:
    
    2.1.3
  - createMessagingErrorMessage
```
protected final java.lang.String createMessagingErrorMessage(java.lang.String description,
                                                             java.lang.Object payload)
```
  - 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.

Class MessagingMessageListenerAdapter<K,​V>

Nested Class Summary

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

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.springframework.kafka.listener.ConsumerSeekAware

Field Detail

NULL_MESSAGE

logger

Constructor Detail

MessagingMessageListenerAdapter

Method Detail

setMessageConverter

getMessageConverter

getType

setFallbackType

setHandlerMethod

isConsumerRecordList

isConsumerRecords

isConversionNeeded

setReplyTopic

setReplyTemplate

setBeanResolver

isMessageList

getReplyHeadersConfigurer

setReplyHeadersConfigurer

isSplitIterables

setSplitIterables

registerSeekCallback

onPartitionsAssigned

onPartitionsRevoked

onIdleContainer

toMessagingMessage

invokeHandler

handleResult

sendResponse

createMessagingErrorMessage

determineInferredType

Class MessagingMessageListenerAdapter<K,V>