Package org.axonframework.modelling.entity

Class EntityCommandHandlingComponent<ID,E>

java.lang.Object

org.axonframework.modelling.entity.EntityCommandHandlingComponent<ID,E>

Type Parameters:

ID - The type of the identifier of the entity.

E - The type of the entity.

All Implemented Interfaces:

DescribableComponent, CommandHandler, CommandHandlingComponent, MessageHandler

public class EntityCommandHandlingComponent<ID,E>
extends Object
implements CommandHandlingComponent, DescribableComponent

A CommandHandlingComponent that handles commands for an entity.

It will resolve the identifier of the entity through the provided EntityIdResolver, load it from the provided Repository and delegate the handling of the command to the EntityMetamodel of the entity.

Since:

5.0.0

Author:

Mitchell Herrijgers

Constructor Summary

Constructors

Constructor	Description
EntityCommandHandlingComponent(Repository<ID,E> repository, EntityMetamodel<E> metamodel, EntityIdResolver<ID> idResolver)	Creates a new CommandHandlingComponent that handles commands for the given entity type.

Method Summary

Modifier and Type	Method	Description
void	describeTo(ComponentDescriptor descriptor)	Describe the properties of this DescribableComponent with the given descriptor.
MessageStream.Single<CommandResultMessage>	handle(CommandMessage command, ProcessingContext context)	Handles the given command within the given context.
Set<QualifiedName>	supportedCommands()	All supported commands, referenced through a QualifiedName.

Methods inherited from class java.lang.Object

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

Constructor Details

EntityCommandHandlingComponent

public EntityCommandHandlingComponent(@Nonnull
 Repository<ID,E> repository,
 @Nonnull
 EntityMetamodel<E> metamodel,
 @Nonnull
 EntityIdResolver<ID> idResolver)

Creates a new CommandHandlingComponent that handles commands for the given entity type.

Parameters:

repository - The Repository to load the entity from.

metamodel - The EntityMetamodel to delegate the handling of the command to.

idResolver - The EntityIdResolver to resolve the identifier of the entity.

Method Details

supportedCommands

public Set<QualifiedName> supportedCommands()

Description copied from interface: CommandHandlingComponent

All supported commands, referenced through a QualifiedName.

Specified by:

supportedCommands in interface CommandHandlingComponent

Returns:

All supported commands, referenced through a QualifiedName.

handle

@Nonnull
public MessageStream.Single<CommandResultMessage> handle(@Nonnull
 CommandMessage command,
 @Nonnull
 ProcessingContext context)

Description copied from interface: CommandHandler

Handles the given command within the given context.

The result message in the returned stream may be null. Only a single or empty result message should ever be expected.

Specified by:

handle in interface CommandHandler

Parameters:

command - The command to handle.

context - The context to the given command is handled in.

Returns:

A MessagesStream.Single of a CommandResultMessage.

describeTo

public void describeTo(@Nonnull
 ComponentDescriptor descriptor)

Description copied from interface: DescribableComponent

Describe the properties of this DescribableComponent with the given descriptor.

Components should call the appropriate describeProperty methods on the descriptor to register their properties. The descriptor is responsible for determining how these properties are formatted and structured in the final output.

Best Practices: As a general rule, all relevant fields of a DescribableComponent implementation should be described in this method. However, developers have discretion to include only the fields that make sense in the context. Not every field may be meaningful for description purposes, especially internal implementation details. Furthermore, components might want to expose different information based on their current state. The final decision on what properties to include lies with the person implementing the describeTo method, who should focus on providing information that is useful for understanding the component's configuration and state.

Example implementation:

 public void describeTo(ComponentDescriptor descriptor) {
     descriptor.describeProperty("name", this.name);
     descriptor.describeProperty("enabled", this.enabled);
     descriptor.describeProperty("configuration", this.configuration); // A nested component
     descriptor.describeProperty("handlers", this.eventHandlers);      // A collection
 }
 

Specified by:

describeTo in interface DescribableComponent

Parameters:

descriptor - The component descriptor to describe this DescribableComponentn its properties in.