Package org.axonframework.messaging.eventhandling.processing.subscribing

Class SubscribingEventProcessorConfiguration

java.lang.Object

org.axonframework.messaging.eventhandling.configuration.EventProcessorConfiguration

org.axonframework.messaging.eventhandling.processing.subscribing.SubscribingEventProcessorConfiguration

All Implemented Interfaces:

DescribableComponent

public class SubscribingEventProcessorConfiguration
extends EventProcessorConfiguration

Configuration class for a SubscribingEventProcessor.

ErrorHandler is defaulted to a PropagatingErrorHandler and the UnitOfWorkFactory defaults to the SimpleUnitOfWorkFactory. The Event Processor SubscribableEventSource is hard requirements and as such should be provided.

Since:

5.0.0

Author:

Mateusz Nowak

Field Summary

Fields inherited from class org.axonframework.messaging.eventhandling.configuration.EventProcessorConfiguration

errorHandler, interceptors, messageMonitor, unitOfWorkFactory

Constructor Summary

Constructors

Constructor	Description
SubscribingEventProcessorConfiguration()	Constructs a new SubscribingEventProcessorConfiguration.
SubscribingEventProcessorConfiguration(EventProcessorConfiguration base)	Constructs a new SubscribingEventProcessorConfiguration copying properties from the given configuration.
SubscribingEventProcessorConfiguration(EventProcessorConfiguration base, Configuration configuration)	Constructs a new SubscribingEventProcessorConfiguration with default values and retrieve global default values.

Method Summary

Modifier and Type	Method	Description
void	describeTo(ComponentDescriptor descriptor)	Describe the properties of this DescribableComponent with the given descriptor.
SubscribingEventProcessorConfiguration	errorHandler(ErrorHandler errorHandler)	Sets the ErrorHandler invoked when an UnitOfWork throws an exception during processing.
SubscribableEventSource	eventSource()	Returns the SubscribableEventSource to which this processor subscribes.
SubscribingEventProcessorConfiguration	eventSource(SubscribableEventSource eventSource)	Sets the SubscribableEventSource (e.g. the EventBus) to which this EventProcessor implementation will subscribe itself to receive EventMessages.
Consumer<? super EventMessage>	ignoredMessageHandler()	Returns the handler for ignored messages.
SubscribingEventProcessorConfiguration	ignoredMessageHandler(Consumer<? super EventMessage> ignoredMessageHandler)	Sets the handler, that is invoked when the event is ignored by all EventHandlingComponents this SubscribingEventProcessor controls.
SubscribingEventProcessorConfiguration	unitOfWorkFactory(UnitOfWorkFactory unitOfWorkFactory)	A UnitOfWorkFactory that spawns UnitOfWork used to process an event batch.
protected void	validate()	Validates whether the fields contained in this Builder are set accordingly.
SubscribingEventProcessorConfiguration	withInterceptor(MessageHandlerInterceptor<? super EventMessage> interceptor)	Registers the given EventMessage-specific MessageHandlerInterceptor for the SubscribingEventProcessor under construction.

Methods inherited from class org.axonframework.messaging.eventhandling.configuration.EventProcessorConfiguration

errorHandler, interceptors, streaming, unitOfWorkFactory

Methods inherited from class java.lang.Object

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

Constructor Details

SubscribingEventProcessorConfiguration

@Internal
public SubscribingEventProcessorConfiguration()

Constructs a new SubscribingEventProcessorConfiguration.

This configuration will not have any of the default MessageHandlerInterceptors for events. Please use SubscribingEventProcessorConfiguration(EventProcessorConfiguration, Configuration) when those are desired.

SubscribingEventProcessorConfiguration

@Internal
public SubscribingEventProcessorConfiguration(@Nonnull
 EventProcessorConfiguration base)

Constructs a new SubscribingEventProcessorConfiguration copying properties from the given configuration.

Parameters:

base - The EventProcessorConfiguration to copy properties from.

SubscribingEventProcessorConfiguration

@Internal
public SubscribingEventProcessorConfiguration(@Nonnull
 EventProcessorConfiguration base,
 @Nonnull
 Configuration configuration)

Constructs a new SubscribingEventProcessorConfiguration with default values and retrieve global default values.

Parameters:

configuration - The configuration, used to retrieve global default values, like MessageHandlerInterceptors, from.

Method Details

errorHandler

public SubscribingEventProcessorConfiguration errorHandler(@Nonnull
 ErrorHandler errorHandler)

Description copied from class: EventProcessorConfiguration

Sets the ErrorHandler invoked when an UnitOfWork throws an exception during processing. Defaults to a PropagatingErrorHandler.

Overrides:

errorHandler in class EventProcessorConfiguration

Parameters:

errorHandler - the ErrorHandler invoked when an UnitOfWork throws an exception during processing

Returns:

The current instance, for fluent interfacing.

eventSource

public SubscribingEventProcessorConfiguration eventSource(@Nonnull
 SubscribableEventSource eventSource)

Sets the SubscribableEventSource (e.g. the EventBus) to which this EventProcessor implementation will subscribe itself to receive EventMessages.

Parameters:

eventSource - The SubscribableEventSource (e.g. the EventBus) to which this EventProcessor implementation will subscribe itself to receive EventMessages.

Returns:

The current instance, for fluent interfacing.

ignoredMessageHandler

public SubscribingEventProcessorConfiguration ignoredMessageHandler(Consumer<? super EventMessage> ignoredMessageHandler)

Sets the handler, that is invoked when the event is ignored by all EventHandlingComponents this SubscribingEventProcessor controls. Defaults to a no-op.

Parameters:

ignoredMessageHandler - The handler, that is invoked when the event is ignored by all EventHandlingComponents this

invalid @link

{@link {@link

SubscribingEventProcessor}} controls.

Returns:

The current Builder instance, for fluent interfacing.

unitOfWorkFactory

public SubscribingEventProcessorConfiguration unitOfWorkFactory(@Nonnull
 UnitOfWorkFactory unitOfWorkFactory)

Description copied from class: EventProcessorConfiguration

A UnitOfWorkFactory that spawns UnitOfWork used to process an event batch.

Overrides:

unitOfWorkFactory in class EventProcessorConfiguration

Parameters:

unitOfWorkFactory - A UnitOfWorkFactory that spawns UnitOfWork.

Returns:

The current instance, for fluent interfacing.

withInterceptor

@Nonnull
public SubscribingEventProcessorConfiguration withInterceptor(@Nonnull
 MessageHandlerInterceptor<? super EventMessage> interceptor)

Registers the given EventMessage-specific MessageHandlerInterceptor for the SubscribingEventProcessor under construction.

Parameters:

interceptor - The EventMessage-specific MessageHandlerInterceptor to register for the SubscribingEventProcessor under construction.

Returns:

This SubscribingEventProcessorConfiguration, for fluent interfacing.

validate

protected void validate()
                 throws AxonConfigurationException

Validates whether the fields contained in this Builder are set accordingly.

Overrides:

validate in class EventProcessorConfiguration

Throws:

AxonConfigurationException - if one field is asserted to be incorrect according to the Builder's specifications.

eventSource

public SubscribableEventSource eventSource()

Returns the SubscribableEventSource to which this processor subscribes.

Returns:

The SubscribableEventSource for receiving events.

ignoredMessageHandler

public Consumer<? super EventMessage> ignoredMessageHandler()

Returns the handler for ignored messages.

Returns:

The ignored message handler.

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

Overrides:

describeTo in class EventProcessorConfiguration

Parameters:

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