org.springframework.integration.splitter

Class AbstractMessageSplitter

java.lang.Object

org.springframework.integration.context.IntegrationObjectSupport

org.springframework.integration.handler.MessageHandlerSupport

org.springframework.integration.handler.AbstractMessageHandler

org.springframework.integration.handler.AbstractMessageProducingHandler

org.springframework.integration.handler.AbstractReplyProducingMessageHandler

org.springframework.integration.splitter.AbstractMessageSplitter

All Implemented Interfaces:

org.reactivestreams.Subscriber<Message<?>>, Aware, BeanClassLoaderAware, BeanFactoryAware, BeanNameAware, DisposableBean, InitializingBean, ApplicationContextAware, Ordered, ExpressionCapable, Orderable, MessageProducer, DiscardingMessageHandler, HeaderPropagationAware, IntegrationPattern, NamedComponent, IntegrationManagement, TrackableComponent, MessageHandler, reactor.core.CoreSubscriber<Message<?>>

Direct Known Subclasses:

DefaultMessageSplitter, ExpressionEvaluatingSplitter, FileSplitter, MethodInvokingSplitter, XPathMessageSplitter

public abstract class AbstractMessageSplitter
extends AbstractReplyProducingMessageHandler
implements DiscardingMessageHandler

Base class for Message-splitting handlers.

Author:

Mark Fisher, Dave Syer, Artem Bilan, Ruslan Stelmachenko, Gary Russell

Nested Class Summary

Nested classes/interfaces inherited from class org.springframework.integration.handler.AbstractReplyProducingMessageHandler

AbstractReplyProducingMessageHandler.RequestHandler

Nested classes/interfaces inherited from interface org.springframework.integration.support.management.IntegrationManagement

IntegrationManagement.ManagementOverrides

Field Summary

Fields inherited from class org.springframework.integration.handler.AbstractMessageProducingHandler

messagingTemplate

Fields inherited from class org.springframework.integration.context.IntegrationObjectSupport

EXPRESSION_PARSER, logger

Fields inherited from interface org.springframework.core.Ordered

HIGHEST_PRECEDENCE, LOWEST_PRECEDENCE

Fields inherited from interface org.springframework.integration.support.management.IntegrationManagement

METER_PREFIX, RECEIVE_COUNTER_NAME, SEND_TIMER_NAME

Constructor Summary

Constructors

Constructor and Description
AbstractMessageSplitter()

Method Summary

Modifier and Type	Method and Description
protected void	addHeaders(Message<?> message, Map<String,Object> headers) Allows subclasses to add extra headers to the output messages.
protected void	doInit()
String	getComponentType() Subclasses may implement this method to provide component type information.
MessageChannel	getDiscardChannel() Return the discard channel.
IntegrationPatternType	getIntegrationPatternType() Return a pattern type this component implements.
protected Object	handleRequestMessage(Message<?> message) Subclasses must implement this method to handle the request Message.
protected int	obtainSizeIfPossible(Iterable<?> iterable) Obtain a size of the provided Iterable.
protected int	obtainSizeIfPossible(Iterator<?> iterator) Obtain a size of the provided Iterator.
protected void	produceOutput(Object result, Message<?> requestMessage)
void	setApplySequence(boolean applySequence) Set the applySequence flag to the specified value.
void	setDiscardChannel(MessageChannel discardChannel) Specify a channel where rejected Messages should be sent.
void	setDiscardChannelName(String discardChannelName) Specify a channel bean name (resolved to MessageChannel lazily) where rejected Messages should be sent.
protected boolean	shouldCopyRequestHeaders() Subclasses may override this.
protected abstract Object	splitMessage(Message<?> message) Subclasses must override this method to split the received Message.
protected boolean	willAddHeaders(Message<?> message) Return true if the subclass needs to add headers in the resulting splits.

Methods inherited from class org.springframework.integration.handler.AbstractReplyProducingMessageHandler

doInvokeAdvisedRequestHandler, getBeanClassLoader, getRequiresReply, handleMessageInternal, hasAdviceChain, onInit, setAdviceChain, setBeanClassLoader, setRequiresReply

Methods inherited from class org.springframework.integration.handler.AbstractMessageProducingHandler

addNotPropagatedHeaders, createOutputMessage, getNotPropagatedHeaders, getOutputChannel, isAsync, messageBuilderForReply, resolveErrorChannel, sendErrorMessage, sendOutput, sendOutputs, setAsync, setNotPropagatedHeaders, setOutputChannel, setOutputChannelName, setSendTimeout, shouldSplitOutput, updateNotPropagatedHeaders

Methods inherited from class org.springframework.integration.handler.AbstractMessageHandler

handleMessage, onComplete, onError, onNext, onSubscribe

Methods inherited from class org.springframework.integration.handler.MessageHandlerSupport

buildSendTimer, destroy, getManagedName, getManagedType, getMetricsCaptor, getOrder, getOverrides, isLoggingEnabled, registerMetricsCaptor, sendTimer, setLoggingEnabled, setManagedName, setManagedType, setOrder, setShouldTrack, shouldTrack

Methods inherited from class org.springframework.integration.context.IntegrationObjectSupport

afterPropertiesSet, extractTypeIfPossible, generateId, getApplicationContext, getApplicationContextId, getBeanDescription, getBeanFactory, getBeanName, getChannelResolver, getComponentName, getConversionService, getExpression, getIntegrationProperties, getIntegrationProperty, getMessageBuilderFactory, getTaskScheduler, isInitialized, setApplicationContext, setBeanFactory, setBeanName, setChannelResolver, setComponentName, setConversionService, setMessageBuilderFactory, setPrimaryExpression, setTaskScheduler, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.messaging.MessageHandler

handleMessage

Methods inherited from interface reactor.core.CoreSubscriber

currentContext

Methods inherited from interface org.springframework.integration.support.management.IntegrationManagement

getThisAs

Methods inherited from interface org.springframework.integration.support.context.NamedComponent

getBeanName, getComponentName

Constructor Detail

AbstractMessageSplitter

public AbstractMessageSplitter()

Method Detail

setApplySequence

public void setApplySequence(boolean applySequence)

Set the applySequence flag to the specified value. Defaults to true.

Parameters:

applySequence - true to apply sequence information.

setDiscardChannel

public void setDiscardChannel(MessageChannel discardChannel)

Specify a channel where rejected Messages should be sent. If the discard channel is null (the default), rejected Messages will be dropped. A "Rejected Message" means that split function has returned an empty result (but not null): no items to iterate for sending.

Parameters:

discardChannel - The discard channel.

Since:

5.2

setDiscardChannelName

public void setDiscardChannelName(String discardChannelName)

Specify a channel bean name (resolved to MessageChannel lazily) where rejected Messages should be sent. If the discard channel is null (the default), rejected Messages will be dropped. A "Rejected Message" means that split function has returned an empty result (but not null): no items to iterate for sending.

Parameters:

discardChannelName - The discard channel bean name.

Since:

5.2

getDiscardChannel

public MessageChannel getDiscardChannel()

Description copied from interface: DiscardingMessageHandler

Return the discard channel.

Specified by:

getDiscardChannel in interface DiscardingMessageHandler

Returns:

the channel.

getIntegrationPatternType

public IntegrationPatternType getIntegrationPatternType()

Description copied from interface: IntegrationPattern

Return a pattern type this component implements.

Specified by:

getIntegrationPatternType in interface IntegrationPattern

Overrides:

getIntegrationPatternType in class AbstractReplyProducingMessageHandler

Returns:

the IntegrationPatternType this component implements.

doInit

protected void doInit()

Overrides:

doInit in class AbstractReplyProducingMessageHandler

handleRequestMessage

protected final Object handleRequestMessage(Message<?> message)

Description copied from class: AbstractReplyProducingMessageHandler

Subclasses must implement this method to handle the request Message. The return value may be a Message, a MessageBuilder, or any plain Object. The base class will handle the final creation of a reply Message from any of those starting points. If the return value is null, the Message flow will end here.

Specified by:

handleRequestMessage in class AbstractReplyProducingMessageHandler

Parameters:

message - The request message.

Returns:

The result of handling the message, or null.

obtainSizeIfPossible

protected int obtainSizeIfPossible(Iterable<?> iterable)

Obtain a size of the provided Iterable. Default implementation returns Collection.size() if the iterable is a collection, or 0 otherwise. If iterable is a Jackson TreeNode, then its size is used.

Parameters:

iterable - the Iterable to obtain the size

Returns:

the size of the Iterable

Since:

5.0

obtainSizeIfPossible

protected int obtainSizeIfPossible(Iterator<?> iterator)

Obtain a size of the provided Iterator. Default implementation returns 0.

Parameters:

iterator - the Iterator to obtain the size

Returns:

the size of the Iterator

Since:

5.0

willAddHeaders

protected boolean willAddHeaders(Message<?> message)

Return true if the subclass needs to add headers in the resulting splits. If true, addHeaders(org.springframework.messaging.Message<?>, java.util.Map<java.lang.String, java.lang.Object>) will be called.

Parameters:

message - the message.

Returns:

true

addHeaders

protected void addHeaders(Message<?> message,
                          Map<String,Object> headers)

Allows subclasses to add extra headers to the output messages. Headers may not be removed by this method.

Parameters:

message - the inbound message.

headers - the headers to add messages to.

shouldCopyRequestHeaders

protected boolean shouldCopyRequestHeaders()

Description copied from class: AbstractMessageProducingHandler

Subclasses may override this. True by default.

Overrides:

shouldCopyRequestHeaders in class AbstractMessageProducingHandler

Returns:

true if the request headers should be copied.

produceOutput

protected void produceOutput(Object result,
                             Message<?> requestMessage)

Overrides:

produceOutput in class AbstractMessageProducingHandler

getComponentType

public String getComponentType()

Description copied from class: IntegrationObjectSupport

Subclasses may implement this method to provide component type information.

Specified by:

getComponentType in interface NamedComponent

Overrides:

getComponentType in class MessageHandlerSupport

splitMessage

protected abstract Object splitMessage(Message<?> message)

Subclasses must override this method to split the received Message. The return value may be a Collection or Array. The individual elements may be Messages, but it is not necessary. If the elements are not Messages, each will be provided as the payload of a Message. It is also acceptable to return a single Object or Message. In that case, a single reply Message will be produced.

Parameters:

message - The message.

Returns:

The result of splitting the message.