Package org.axonframework.modelling.saga

Class AnnotatedSagaManager<T>

java.lang.Object

org.axonframework.modelling.saga.AbstractSagaManager<T>

org.axonframework.modelling.saga.AnnotatedSagaManager<T>

Type Parameters:

T - The type of Saga managed by this instance

All Implemented Interfaces:

DescribableComponent, MessageHandler, EventHandler, EventHandlingComponent, ReplayStatusChangedHandler, ResetHandler, ScopeAware

public class AnnotatedSagaManager<T>
extends AbstractSagaManager<T>

Implementation of the SagaManager that uses annotations on the Sagas to describe the lifecycle management. This implementation can manage several types of Saga in a single AnnotatedSagaManager.

Since:

0.7

Author:

Allard Buijze

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AnnotatedSagaManager.Builder<T>	Builder class to instantiate a AnnotatedSagaManager.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AnnotatedSagaManager(AnnotatedSagaManager.Builder<T> builder)	Instantiate a AnnotatedSagaManager based on the fields contained in the AnnotatedSagaManager.Builder.

Method Summary

Modifier and Type	Method	Description
static <T> AnnotatedSagaManager.Builder<T>	builder()	Instantiate a Builder to be able to create a AnnotatedSagaManager.
protected boolean	canHandle(EventMessage event, ProcessingContext context)	Indicates whether a Saga of the given sagaType has a handler for the given event.
protected Set<AssociationValue>	extractAssociationValues(EventMessage event, ProcessingContext context)	Extracts the AssociationValues from the given event as relevant for a Saga of given sagaType.
protected SagaInitializationPolicy	getSagaCreationPolicy(EventMessage event, ProcessingContext context)	Returns the Saga Initialization Policy for a Saga of the given sagaType and event.
Set<QualifiedName>	supportedEvents()	All supported events, referenced through a QualifiedName.
protected EventMessage	withHandlerPayload(EventMessage event, ProcessingContext context)	Returns the given event with its payload converted to the type the Saga's handler declares for it.

Methods inherited from class org.axonframework.modelling.saga.AbstractSagaManager

canResolve, createSagaIdentifier, describeTo, getSagaType, handle, handle, matchesSegment, send, sequenceIdentifierFor, supportsReset

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.axonframework.messaging.eventhandling.EventHandlingComponent

handle, supports, unwrap

Constructor Details

AnnotatedSagaManager

protected AnnotatedSagaManager(AnnotatedSagaManager.Builder<T> builder)

Instantiate a AnnotatedSagaManager based on the fields contained in the AnnotatedSagaManager.Builder.

The sagaFactory is defaulted to a sagaType.newInstance() call throwing a SagaInstantiationException if it fails. The SagaRepository and sagaType are hard requirements and as such should be provided.

Will assert that the SagaRepository, sagaType and sagaFactory are not null, and will throw an AxonConfigurationException if any of them is null. Additionally, the provided Builder's goal is to either build a SagaModel specifying generic T as the Saga type to be stored or derive it based on the given sagaType. All Sagas managed by this Saga manager must be instanceOf this Saga type.

Parameters:

builder - the AnnotatedSagaManager.Builder used to instantiate a AnnotatedSagaManager instance

Method Details

builder

public static <T> AnnotatedSagaManager.Builder<T> builder()

Instantiate a Builder to be able to create a AnnotatedSagaManager.

The sagaFactory is defaulted to a sagaType.newInstance() call throwing a SagaInstantiationException if it fails.

This Builder either allows directly setting a SagaModel of generic type T, or it will generate one based of the required sagaType field of type Class. Thus, either the SagaModel or the sagaType should be provided. All Sagas managed by this instances must be instanceOf this saga type. Additionally, the SagaRepository and sagaType are hard requirements and as such should be provided.

Type Parameters:

T - a generic specifying the Saga type managed by this AbstractSagaManager implementation

Returns:

a Builder to be able to create a AnnotatedSagaManager

canHandle

protected boolean canHandle(EventMessage event,
 ProcessingContext context)

Description copied from class: AbstractSagaManager

Indicates whether a Saga of the given sagaType has a handler for the given event.

This check is independent of the Message.type(): Sagas resolve their handlers by inspecting the payload's runtime type, the same way a @SagaEventHandler method is matched, since the message name carried by a MessageType is not guaranteed to correlate with the payload's class. That makes it stricter than EventHandlingComponent.supports(QualifiedName), which the EventProcessor consults before it delivers an event, so this method is asked again on the way in.

This is a question about the Saga type, not about any one instance. For the instance-level question, see Saga.canHandle(EventMessage, ProcessingContext).

Specified by:

canHandle in class AbstractSagaManager<T>

Parameters:

event - The event to check for a handler.

context - The ProcessingContext in which the event is being processed.

Returns:

true if a Saga of the given sagaType has a handler for the given event, false otherwise.

supportedEvents

public Set<QualifiedName> supportedEvents()

Description copied from interface: EventHandlingComponent

All supported events, referenced through a QualifiedName.

Specified by:

supportedEvents in interface EventHandlingComponent

Specified by:

supportedEvents in class AbstractSagaManager<T>

Returns:

All supported events, referenced through a QualifiedName.

getSagaCreationPolicy

protected SagaInitializationPolicy getSagaCreationPolicy(EventMessage event,
 ProcessingContext context)

Description copied from class: AbstractSagaManager

Returns the Saga Initialization Policy for a Saga of the given sagaType and event. This policy provides the conditions to create new Saga instance, as well as the initial association of that saga.

Specified by:

getSagaCreationPolicy in class AbstractSagaManager<T>

Parameters:

event - The Event that is being dispatched to Saga instances.

context - The ProcessingContext in which the event is being processed.

Returns:

The initialization policy for the Saga.

withHandlerPayload

protected EventMessage withHandlerPayload(EventMessage event,
 ProcessingContext context)

Description copied from class: AbstractSagaManager

Returns the given event with its payload converted to the type the Saga's handler declares for it.

Events read from an event store carry a serialized payload. Handler matching and association resolution work on the payload's runtime type, so without this step every such event is ignored. Events whose payload already has the handler's type, and events no handler is declared for, are returned unchanged.

Specified by:

withHandlerPayload in class AbstractSagaManager<T>

Parameters:

event - the event to convert

context - the ProcessingContext providing the EventConverter

Returns:

the event with a converted payload, or the given event

extractAssociationValues

protected Set<AssociationValue> extractAssociationValues(EventMessage event,
 ProcessingContext context)

Description copied from class: AbstractSagaManager

Extracts the AssociationValues from the given event as relevant for a Saga of given sagaType. A single event may be associated with multiple values.

Specified by:

extractAssociationValues in class AbstractSagaManager<T>

Parameters:

event - The event containing the association information.

context - The ProcessingContext in which the event is being processed.

Returns:

The AssociationValues indicating which Sagas should handle given event.