org.axonframework.commandhandling.distributed

Class AnnotationRoutingStrategy

java.lang.Object

org.axonframework.commandhandling.distributed.AbstractRoutingStrategy

org.axonframework.commandhandling.distributed.AnnotationRoutingStrategy

All Implemented Interfaces:

RoutingStrategy

public class AnnotationRoutingStrategy
extends AbstractRoutingStrategy

RoutingStrategy that expects an RoutingKey (meta-)annotation on the command message's payload. Commands are routed based on an identifier annotated with the RoutingKey. This approach ensures that commands with the same identifier, thus dealt with by the same target, are dispatched to the same node in a DistributedCommandBus.

An example would be the TargetAggregateIdentifier annotation, which is meta-annotated with RoutingKey. See the AnnotationCommandTargetResolver for more details on this approach.

This class requires the returned routing keys to implement a proper Object.toString() method. An inconsistent toString() method may result in different members using different routing keys for the same identifier.

Since:

2.0

Author:

Allard Buijze

See Also:

DistributedCommandBus

Constructor Summary

Constructors

Constructor and Description
AnnotationRoutingStrategy() Initializes a Routing Strategy that fails when an incoming command does not define a field as the RoutingKey to base the routing on.
AnnotationRoutingStrategy(Class<? extends Annotation> annotationType) Initializes a Routing Strategy that uses the given annotation to resolve the targeted identifier.
AnnotationRoutingStrategy(Class<? extends Annotation> annotationType, UnresolvedRoutingKeyPolicy unresolvedRoutingKeyPolicy) Initializes a Routing Strategy that uses the given annotation to resolve the targeted identifier and the given unresolvedRoutingKeyPolicy when an incoming command does not define an Identifier to base the routing key on.
AnnotationRoutingStrategy(UnresolvedRoutingKeyPolicy unresolvedRoutingKeyPolicy) Initializes a Routing Strategy that uses the given unresolvedRoutingKeyPolicy when an incoming command does not define a RoutingKey annotated field to base the routing on.

Method Summary

Modifier and Type	Method and Description
protected String	doResolveRoutingKey(CommandMessage<?> command) Resolve the Routing Key for the given command.

Methods inherited from class org.axonframework.commandhandling.distributed.AbstractRoutingStrategy

getRoutingKey

Methods inherited from class java.lang.Object

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

Constructor Detail

AnnotationRoutingStrategy

public AnnotationRoutingStrategy()

Initializes a Routing Strategy that fails when an incoming command does not define a field as the RoutingKey to base the routing on.

AnnotationRoutingStrategy

public AnnotationRoutingStrategy(Class<? extends Annotation> annotationType)

Initializes a Routing Strategy that uses the given annotation to resolve the targeted identifier.

Parameters:

annotationType - the type of annotation marking the field or method providing the identifier of the targeted model

AnnotationRoutingStrategy

public AnnotationRoutingStrategy(UnresolvedRoutingKeyPolicy unresolvedRoutingKeyPolicy)

Initializes a Routing Strategy that uses the given unresolvedRoutingKeyPolicy when an incoming command does not define a RoutingKey annotated field to base the routing on.

Parameters:

unresolvedRoutingKeyPolicy - a UnresolvedRoutingKeyPolicy indicating what should be done when a Command does not contain information about the routing key to use

AnnotationRoutingStrategy

public AnnotationRoutingStrategy(Class<? extends Annotation> annotationType,
                                 UnresolvedRoutingKeyPolicy unresolvedRoutingKeyPolicy)

Initializes a Routing Strategy that uses the given annotation to resolve the targeted identifier and the given unresolvedRoutingKeyPolicy when an incoming command does not define an Identifier to base the routing key on.

Parameters:

annotationType - the type of annotation marking the field or method providing the identifier of the targeted model

unresolvedRoutingKeyPolicy - a UnresolvedRoutingKeyPolicy indicating what should be done when a Command does not contain information about the routing key to use

Method Detail

doResolveRoutingKey

protected String doResolveRoutingKey(CommandMessage<?> command)

Description copied from class: AbstractRoutingStrategy

Resolve the Routing Key for the given command.

Specified by:

doResolveRoutingKey in class AbstractRoutingStrategy

Parameters:

command - The command to resolve the routing key for

Returns:

the String representing the Routing Key, or null if unresolved.