Package org.axonframework.messaging.eventhandling.configuration

Class EventProcessorConfiguration

java.lang.Object

org.axonframework.messaging.eventhandling.configuration.EventProcessorConfiguration

All Implemented Interfaces:

DescribableComponent

Direct Known Subclasses:

PooledStreamingEventProcessorConfiguration, SubscribingEventProcessorConfiguration

public class EventProcessorConfiguration
extends Object
implements DescribableComponent

Configuration class to be used for EventProcessor implementations.

The ErrorHandler is defaulted to a PropagatingErrorHandler and the UnitOfWorkFactory defaults to the SimpleUnitOfWorkFactory

Since:

5.0.0

Author:

Mateusz Nowak

Field Summary

Fields

Modifier and Type	Field	Description
protected ErrorHandler	errorHandler
protected BiFunction<Class<? extends EventProcessor>,String,List<MessageHandlerInterceptor<? super EventMessage>>>	interceptorBuilder
protected List<MessageHandlerInterceptor<? super EventMessage>>	interceptors
protected BiFunction<Class<? extends EventProcessor>,String,MessageMonitor<? super EventMessage>>	monitorBuilder
protected final String	processorName
protected UnitOfWorkFactory	unitOfWorkFactory

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method	Description
void	describeTo(ComponentDescriptor descriptor)	Describe the properties of this DescribableComponent with the given descriptor.
ErrorHandler	errorHandler()	Returns the ErrorHandler invoked when an UnitOfWork throws an exception during processing.
EventProcessorConfiguration	errorHandler(ErrorHandler errorHandler)	Sets the ErrorHandler invoked when an UnitOfWork throws an exception during processing.
boolean	streaming()	Returns whether this configuration is for a streaming event processor.
UnitOfWorkFactory	unitOfWorkFactory()	Returns the UnitOfWorkFactory used to create UnitOfWork instances for event processing.
EventProcessorConfiguration	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.

Methods inherited from class java.lang.Object

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

Field Details

processorName

protected final String processorName

errorHandler

protected ErrorHandler errorHandler

unitOfWorkFactory

protected UnitOfWorkFactory unitOfWorkFactory

interceptors

protected List<MessageHandlerInterceptor<? super EventMessage>> interceptors

interceptorBuilder

protected BiFunction<Class<? extends EventProcessor>,String,List<MessageHandlerInterceptor<? super EventMessage>>> interceptorBuilder

monitorBuilder

protected BiFunction<Class<? extends EventProcessor>,String,MessageMonitor<? super EventMessage>> monitorBuilder

Constructor Details

EventProcessorConfiguration

@Internal
public EventProcessorConfiguration(String processorName,
 @Nullable Configuration config)

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

When the given config is null, the MessageHandlerInterceptors and MessageMonitor will not be retrieved from the HandlerInterceptorRegistry and MessageMonitorRegistry respectively.

Parameters:

processorName - the name of the processor this configuration is for

config - the config, used to retrieve global default values, like MessageHandlerInterceptors, from

EventProcessorConfiguration

@Internal
public EventProcessorConfiguration(EventProcessorConfiguration base)

Constructs a new EventProcessorConfiguration copying properties from the given configuration.

Parameters:

base - the EventProcessorConfiguration to copy properties from

Method Details

errorHandler

public EventProcessorConfiguration errorHandler(ErrorHandler errorHandler)

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

Parameters:

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

Returns:

The current instance, for fluent interfacing.

unitOfWorkFactory

public EventProcessorConfiguration unitOfWorkFactory(UnitOfWorkFactory unitOfWorkFactory)

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

Parameters:

unitOfWorkFactory - A UnitOfWorkFactory that spawns UnitOfWork.

Returns:

The current instance, for fluent interfacing.

validate

protected void validate()
                 throws AxonConfigurationException

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

Throws:

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

errorHandler

public ErrorHandler errorHandler()

Returns the ErrorHandler invoked when an UnitOfWork throws an exception during processing.

Returns:

The ErrorHandler for this EventProcessor implementation.

unitOfWorkFactory

public UnitOfWorkFactory unitOfWorkFactory()

Returns the UnitOfWorkFactory used to create UnitOfWork instances for event processing.

Returns:

The UnitOfWorkFactory for this EventProcessor implementation.

streaming

public boolean streaming()

Returns whether this configuration is for a streaming event processor.

Returns:

false for basic configuration, true for streaming configurations.

describeTo

public void describeTo(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.