Package org.axonframework.modelling.entity.child

Class SingleEntityChildMetamodel<C,P>

java.lang.Object

org.axonframework.modelling.entity.child.AbstractEntityChildMetamodel<C,P>

org.axonframework.modelling.entity.child.SingleEntityChildMetamodel<C,P>

Type Parameters:

C - the type of the child entity

P - the type of the parent entity

All Implemented Interfaces:

EntityChildMetamodel<C,P>, EntityEvolver<P>

public class SingleEntityChildMetamodel<C,P>
extends AbstractEntityChildMetamodel<C,P>

An EntityChildMetamodel that handles commands and events for a single child entity.

It will use the provided ChildEntityFieldDefinition to resolve the child entity from the parent entity. Once the entity is resolved, it will delegate the command- and event-handling to the child entity metamodel.

The commands and events will, by default, be forwarded unconditionally to the child entity. If you have multiple member fields, and want to match commands and events to a specific child entity, you can configure the CommandTargetResolver and EventTargetMatcher to match the child entity based on the command or event.

Since:

5.0.0

Author:

Mitchell Herrijgers

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SingleEntityChildMetamodel.Builder<C,P>	Builder for creating a SingleEntityChildMetamodel for the given parent class and child entity metamodel.

Field Summary

Fields inherited from class org.axonframework.modelling.entity.child.AbstractEntityChildMetamodel

commandTargetResolver, eventTargetMatcher, metamodel

Method Summary

Modifier and Type	Method	Description
protected P	applyEvolvedChildEntities(P entity, Map<Object,C> evolvedChildEntities)	Applies the evolved child entities, keyed by the same implementation-specific identity returned by AbstractEntityChildMetamodel.getChildEntities(Object), to the given entity.
EntityMetamodel<C>	entityMetamodel()	Returns the EntityMetamodel of the child entity this metamodel describes.
static <C, P> SingleEntityChildMetamodel.Builder<C,P>	forEntityModel(Class<P> parentClass, EntityMetamodel<C> metamodel)	Creates a new SingleEntityChildMetamodel.Builder for the given parent class and child entity metamodel.
protected Map<Object,C>	getChildEntities(P parent)	Resolves the child entities of the given parent, keyed by an implementation-specific identity.
String	toString()

Methods inherited from class org.axonframework.modelling.entity.child.AbstractEntityChildMetamodel

canHandle, entityType, evolve, handle, supportedCommands

Methods inherited from class java.lang.Object

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

Method Details

getChildEntities

protected Map<Object,C> getChildEntities(P parent)

Description copied from class: AbstractEntityChildMetamodel

Resolves the child entities of the given parent, keyed by an implementation-specific identity.

The returned immutable Map must preserve iteration order (e.g. LinkedHashMap), as that order determines the order in which candidates are offered to the CommandTargetResolver and EventTargetMatcher.

Specified by:

getChildEntities in class AbstractEntityChildMetamodel<C,P>

Parameters:

parent - the parent entity to resolve the child entities from

Returns:

the child entities of the given parent, keyed by an implementation-specific identity

applyEvolvedChildEntities

protected P applyEvolvedChildEntities(P entity,
 Map<Object,C> evolvedChildEntities)

Description copied from class: AbstractEntityChildMetamodel

Applies the evolved child entities, keyed by the same implementation-specific identity returned by AbstractEntityChildMetamodel.getChildEntities(Object), to the given entity. A key that was present in AbstractEntityChildMetamodel.getChildEntities(Object) but is absent from evolvedChildEntities indicates that the corresponding child entity was evolved to null and should be removed.

Specified by:

applyEvolvedChildEntities in class AbstractEntityChildMetamodel<C,P>

Parameters:

entity - the parent entity to apply the evolved child entities to

evolvedChildEntities - the evolved child entities, keyed by the same identity as AbstractEntityChildMetamodel.getChildEntities(Object)

Returns:

the evolved parent entity

entityMetamodel

public EntityMetamodel<C> entityMetamodel()

Description copied from interface: EntityChildMetamodel

Returns the EntityMetamodel of the child entity this metamodel describes.

Returns:

the EntityMetamodel of the child entity this metamodel describes

toString

public String toString()

Overrides:

toString in class Object

forEntityModel

public static <C,
P>
SingleEntityChildMetamodel.Builder<C,P> forEntityModel(Class<P> parentClass,
 EntityMetamodel<C> metamodel)

Creates a new SingleEntityChildMetamodel.Builder for the given parent class and child entity metamodel. The ChildEntityFieldDefinition is required to resolve the child entity from the parent entity and evolve the parent entity based on the child entities.

Type Parameters:

C - the type of the child entity

P - the type of the parent entity

Parameters:

parentClass - the class of the parent entity

metamodel - the EntityMetamodel of the child entity

Returns:

a new SingleEntityChildMetamodel.Builder for the given parent class and child entity metamodel