org.axonframework.eventhandling

Class TrackingEventProcessor.Builder

java.lang.Object

org.axonframework.eventhandling.AbstractEventProcessor.Builder

org.axonframework.eventhandling.TrackingEventProcessor.Builder

Enclosing class:

TrackingEventProcessor

public static class TrackingEventProcessor.Builder
extends AbstractEventProcessor.Builder

Builder class to instantiate a TrackingEventProcessor.

The RollbackConfigurationType defaults to a RollbackConfigurationType.ANY_THROWABLE, the ErrorHandler is defaulted to a PropagatingErrorHandler, the MessageMonitor defaults to a NoOpMessageMonitor and the TrackingEventProcessorConfiguration to a TrackingEventProcessorConfiguration.forSingleThreadedProcessing() call. The Event Processor name, EventHandlerInvoker, StreamableMessageSource, TokenStore and TransactionManager are hard requirements and as such should be provided.

Field Summary

Fields inherited from class org.axonframework.eventhandling.AbstractEventProcessor.Builder

name

Constructor Summary

Constructors

Constructor and Description
Builder()

Method Summary

Modifier and Type	Method and Description
TrackingEventProcessor	build() Initializes a TrackingEventProcessor as specified through this Builder.
TrackingEventProcessor.Builder	errorHandler(ErrorHandler errorHandler) Sets the ErrorHandler invoked when an UnitOfWork is rolled back during processing.
TrackingEventProcessor.Builder	eventHandlerInvoker(EventHandlerInvoker eventHandlerInvoker) Sets the EventHandlerInvoker which will handle all the individual EventMessages.
TrackingEventProcessor.Builder	messageMonitor(MessageMonitor<? super EventMessage<?>> messageMonitor) Sets the MessageMonitor to monitor EventMessages before and after they're processed.
TrackingEventProcessor.Builder	messageSource(StreamableMessageSource<TrackedEventMessage<?>> messageSource) Sets the StreamableMessageSource (e.g.
TrackingEventProcessor.Builder	name(String name) Sets the name of this EventProcessor implementation.
TrackingEventProcessor.Builder	rollbackConfiguration(RollbackConfiguration rollbackConfiguration) Sets the RollbackConfiguration specifying the rollback behavior of the UnitOfWork while processing a batch of events.
TrackingEventProcessor.Builder	storingTokensAfterProcessing() Set this processor to store Tracking Tokens only at the end of processing.
TrackingEventProcessor.Builder	tokenStore(TokenStore tokenStore) Sets the TokenStore used to store and fetch event tokens that enable this EventProcessor to track its progress.
TrackingEventProcessor.Builder	trackingEventProcessorConfiguration(TrackingEventProcessorConfiguration trackingEventProcessorConfiguration) Sets the TrackingEventProcessorConfiguration containing the fine grained configuration options for a TrackingEventProcessor.
TrackingEventProcessor.Builder	transactionManager(TransactionManager transactionManager) Sets the TransactionManager used when processing EventMessages.
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

Constructor Detail

Builder

public Builder()

Method Detail

name

public TrackingEventProcessor.Builder name(String name)

Description copied from class: AbstractEventProcessor.Builder

Sets the name of this EventProcessor implementation.

Overrides:

name in class AbstractEventProcessor.Builder

Parameters:

name - a String defining this EventProcessor implementation

Returns:

the current Builder instance, for fluent interfacing

eventHandlerInvoker

public TrackingEventProcessor.Builder eventHandlerInvoker(EventHandlerInvoker eventHandlerInvoker)

Description copied from class: AbstractEventProcessor.Builder

Sets the EventHandlerInvoker which will handle all the individual EventMessages.

Overrides:

eventHandlerInvoker in class AbstractEventProcessor.Builder

Parameters:

eventHandlerInvoker - the EventHandlerInvoker which will handle all the individual EventMessages

Returns:

the current Builder instance, for fluent interfacing

rollbackConfiguration

public TrackingEventProcessor.Builder rollbackConfiguration(RollbackConfiguration rollbackConfiguration)

Sets the RollbackConfiguration specifying the rollback behavior of the UnitOfWork while processing a batch of events.. Defaults to a RollbackConfigurationType.ANY_THROWABLE)

Overrides:

rollbackConfiguration in class AbstractEventProcessor.Builder

Parameters:

rollbackConfiguration - the RollbackConfiguration specifying the rollback behavior of the UnitOfWork while processing a batch of events.

Returns:

the current Builder instance, for fluent interfacing

errorHandler

public TrackingEventProcessor.Builder errorHandler(ErrorHandler errorHandler)

Description copied from class: AbstractEventProcessor.Builder

Sets the ErrorHandler invoked when an UnitOfWork is rolled back during processing. Defaults to a PropagatingErrorHandler.

Overrides:

errorHandler in class AbstractEventProcessor.Builder

Parameters:

errorHandler - the ErrorHandler invoked when an UnitOfWork is rolled back during processing

Returns:

the current Builder instance, for fluent interfacing

messageMonitor

public TrackingEventProcessor.Builder messageMonitor(MessageMonitor<? super EventMessage<?>> messageMonitor)

Description copied from class: AbstractEventProcessor.Builder

Sets the MessageMonitor to monitor EventMessages before and after they're processed. Defaults to a NoOpMessageMonitor.

Overrides:

messageMonitor in class AbstractEventProcessor.Builder

Parameters:

messageMonitor - a MessageMonitor to monitor EventMessages before and after they're processed

Returns:

the current Builder instance, for fluent interfacing

messageSource

public TrackingEventProcessor.Builder messageSource(StreamableMessageSource<TrackedEventMessage<?>> messageSource)

Sets the StreamableMessageSource (e.g. the EventBus) which this EventProcessor will track.

Parameters:

messageSource - the StreamableMessageSource (e.g. the EventBus) which this EventProcessor will track

Returns:

the current Builder instance, for fluent interfacing

tokenStore

public TrackingEventProcessor.Builder tokenStore(TokenStore tokenStore)

Sets the TokenStore used to store and fetch event tokens that enable this EventProcessor to track its progress.

Parameters:

tokenStore - the TokenStore used to store and fetch event tokens that enable this EventProcessor to track its progress

Returns:

the current Builder instance, for fluent interfacing

transactionManager

public TrackingEventProcessor.Builder transactionManager(TransactionManager transactionManager)

Sets the TransactionManager used when processing EventMessages.

Note that setting this value influences the behavior for storing tokens either at the start or at the end of a batch. If a TransactionManager other than a NoTransactionManager is configured, the default behavior is to store the last token of the Batch to the Token Store before processing of events begins. If the NoTransactionManager is provided, the default is to extend the claim at the start of the unit of work, and update the token after processing Events. When tokens are stored at the start of a batch, a claim extension will be sent at the end of the batch if processing that batch took longer than the tokenClaimUpdateInterval.

Use storingTokensAfterProcessing() to force storage of tokens at the end of a batch.

Parameters:

transactionManager - the TransactionManager used when processing EventMessages

Returns:

the current Builder instance, for fluent interfacing

See Also:

storingTokensAfterProcessing()

trackingEventProcessorConfiguration

public TrackingEventProcessor.Builder trackingEventProcessorConfiguration(TrackingEventProcessorConfiguration trackingEventProcessorConfiguration)

Sets the TrackingEventProcessorConfiguration containing the fine grained configuration options for a TrackingEventProcessor. Defaults to a TrackingEventProcessorConfiguration.forSingleThreadedProcessing() call.

Parameters:

trackingEventProcessorConfiguration - the TrackingEventProcessorConfiguration containing the fine grained configuration options for a TrackingEventProcessor

Returns:

the current Builder instance, for fluent interfacing

storingTokensAfterProcessing

public TrackingEventProcessor.Builder storingTokensAfterProcessing()

Set this processor to store Tracking Tokens only at the end of processing. This has an impact on performance, as the processor will need to extend the claim at the start of the process, and then update the token at the end. This causes 2 round-trips to the Token Store per batch of events.

Enable this when a Token Store cannot participate in a transaction, or when at-most-once-delivery semantics are desired.

The default behavior is to store the last token of the Batch to the Token Store before processing of events begins, if a TransactionManager is configured. If the NoTransactionManager is provided, the default is to extend the claim at the start of the unit of work, and update the token after processing Events. When tokens are stored at the start of a batch, a claim extension will be sent at the end of the batch if processing that batch took longer than the tokenClaimUpdateInterval.

Returns:

the current Builder instance, for fluent interfacing

build

public TrackingEventProcessor build()

Initializes a TrackingEventProcessor as specified through this Builder.

Returns:

a TrackingEventProcessor as specified through this Builder

validate

protected void validate()
                 throws AxonConfigurationException

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

Overrides:

validate in class AbstractEventProcessor.Builder

Throws:

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