Package org.axonframework.messaging.core.interception

Class CorrelationDataInterceptor<M extends Message>

java.lang.Object

org.axonframework.messaging.core.interception.CorrelationDataInterceptor<M>

Type Parameters:

M - The message type this interceptor can process.

All Implemented Interfaces:

MessageDispatchInterceptor<M>, MessageHandlerInterceptor<M>

@Internal
public class CorrelationDataInterceptor<M extends Message>
extends Object
implements MessageDispatchInterceptor<M>, MessageHandlerInterceptor<M>

A MessageDispatchInterceptor and MessageHandlerInterceptor implementation using CorrelationDataProviders to collect and set a collection of correlation data.

The correlation data is registered with the ProcessingContext upon interception of a message under Context.ResourceKey CORRELATION_DATA. On interceptOnDispatch(Message, ProcessingContext, MessageDispatchInterceptorChain), the ProcessingContext is checked for the existence of this resource. When present, the given Message receive the correlation data as additional

invalid reference

org.axonframework.messaging.MetaData

.

Users can expect that this CorrelationDataInterceptor is always set for the user to ensure any correlation data is present at all time.

Since:

3.0.0

Author:

Rene de Waele, Steven van Beelen

Field Summary

Fields

Modifier and Type	Field	Description
static final Context.ResourceKey<Map<String,String>>	CORRELATION_DATA	Resource key the correlation data is stored in the ProcessingContext.

Constructor Summary

Constructors

Constructor	Description
CorrelationDataInterceptor(Collection<CorrelationDataProvider> correlationDataProviders)	Construct a CorrelationDataInterceptor that collects correlation data from intercepted messages with the given correlationDataProviders, and sets it during dispatching
CorrelationDataInterceptor(CorrelationDataProvider... correlationDataProviders)	Construct a CorrelationDataInterceptor that collects correlation data from intercepted messages with the given correlationDataProviders, and sets it during dispatching

Method Summary

Modifier and Type	Method	Description
MessageStream<?>	interceptOnDispatch(M message, ProcessingContext context, MessageDispatchInterceptorChain<M> chain)	Intercepts a given message on dispatching.
MessageStream<?>	interceptOnHandle(M message, ProcessingContext context, MessageHandlerInterceptorChain<M> chain)	Intercepts a given message on handling before reaching the designated MessageHandler.

Methods inherited from class java.lang.Object

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

Field Details

CORRELATION_DATA

public static final Context.ResourceKey<Map<String,String>> CORRELATION_DATA

Resource key the correlation data is stored in the ProcessingContext.

Constructor Details

CorrelationDataInterceptor

public CorrelationDataInterceptor(CorrelationDataProvider... correlationDataProviders)

Construct a CorrelationDataInterceptor that collects correlation data from intercepted messages with the given correlationDataProviders, and sets it during dispatching

Parameters:

correlationDataProviders - The correlation data providers to generate correlation data from intercepted messages.

CorrelationDataInterceptor

public CorrelationDataInterceptor(@Nonnull
 Collection<CorrelationDataProvider> correlationDataProviders)

Construct a CorrelationDataInterceptor that collects correlation data from intercepted messages with the given correlationDataProviders, and sets it during dispatching

Parameters:

correlationDataProviders - The correlation data providers to generate correlation data from intercepted messages.

Method Details

interceptOnDispatch

@Nonnull
public MessageStream<?> interceptOnDispatch(@Nonnull
 M message,
 @Nullable
 ProcessingContext context,
 @Nonnull
 MessageDispatchInterceptorChain<M> chain)

Description copied from interface: MessageDispatchInterceptor

Intercepts a given message on dispatching.

The implementer of this method might want to intercept the message before passing it to the chain (effectively before calling MessageDispatchInterceptorChain.proceed(Message, ProcessingContext)) or after the chain (by mapping the resulting message by calling MessageStream.mapMessage(Function)).

Specified by:

interceptOnDispatch in interface MessageDispatchInterceptor<M extends Message>

Parameters:

message - The message to intercept on dispatching.

context - The active processing context, if any. Can be used to (e.g.) validate correlation data.

chain - The interceptor chain to signal that processing is finished and further interceptors should be called.

Returns:

The resulting message stream from MessageDispatchInterceptorChain.proceed(Message, ProcessingContext).

interceptOnHandle

@Nonnull
public MessageStream<?> interceptOnHandle(@Nonnull
 M message,
 @Nonnull
 ProcessingContext context,
 @Nonnull
 MessageHandlerInterceptorChain<M> chain)

Description copied from interface: MessageHandlerInterceptor

Intercepts a given message on handling before reaching the designated MessageHandler.

The interceptor is responsible for the continuation of the handling process by invoking the MessageHandlerInterceptorChain.proceed(Message, ProcessingContext) method on the given interceptorChain.

The given context contains contextual information. Any information gathered by interceptors may be attached to the context.

Interceptors are not allowed to change the type of the message handling result, as the dispatching component expects a result of a specific type.

Specified by:

interceptOnHandle in interface MessageHandlerInterceptor<M extends Message>

Parameters:

message - The message to intercept on handling.

context - The active processing context of the message being processed.

chain - The interceptor chain that allows this interceptor to proceed the dispatch process.

Returns:

The resulting message stream from MessageHandlerInterceptorChain.proceed(Message, ProcessingContext).