org.axonframework.eventhandling

Class SimpleEventHandlerInvoker.Builder

java.lang.Object

org.axonframework.eventhandling.SimpleEventHandlerInvoker.Builder

Enclosing class:

SimpleEventHandlerInvoker

public static class SimpleEventHandlerInvoker.Builder
extends Object

Builder class to instantiate a SimpleEventHandlerInvoker.

The ListenerInvocationErrorHandler is defaulted to a LoggingErrorHandler and the SequencingPolicy to a SequentialPerAggregatePolicy. Providing at least one Event Handler is a hard requirement and thus should be accounted for.

Constructor Summary

Constructors

Constructor and Description
Builder()

Method Summary

Modifier and Type	Method and Description
SimpleEventHandlerInvoker	build() Initializes a SimpleEventHandlerInvoker as specified through this Builder.
SimpleEventHandlerInvoker.Builder	eventHandlers(List<?> eventHandlers) Sets the eventHandlers this EventHandlerInvoker will forward all its events to.
SimpleEventHandlerInvoker.Builder	eventHandlers(Object... eventHandlers) Sets the eventHandlers this EventHandlerInvoker will forward all its events to.
SimpleEventHandlerInvoker.Builder	handlerDefinition(HandlerDefinition handlerDefinition) Sets the HandlerDefinition used to create concrete handlers in the annotated handlers in the AnnotationEventHandlerAdapter this EventHandlerInvoker instantiates.
SimpleEventHandlerInvoker.Builder	listenerInvocationErrorHandler(ListenerInvocationErrorHandler listenerInvocationErrorHandler) Sets the ListenerInvocationErrorHandler which deals with any Exceptions being thrown by the EventListeners.
SimpleEventHandlerInvoker.Builder	parameterResolverFactory(ParameterResolverFactory parameterResolverFactory) Sets the ParameterResolverFactory used to resolve parameter values for annotated handlers in the AnnotationEventHandlerAdapter this EventHandlerInvoker instantiates.
SimpleEventHandlerInvoker.Builder	sequencingPolicy(SequencingPolicy<? super EventMessage<?>> sequencingPolicy) Sets the SequencingPolicy in charge of deciding whether a given event should be handled (through SimpleEventHandlerInvoker.handle(EventMessage, Segment)) by the given Segment.
protected void	validate() Validates whether the fields contained in this Builder are set accordingly.
AnnotationEventHandlerAdapter	wrapEventMessageHandler(Object eventHandler) Wrap a given eventHandler in an AnnotationEventHandlerAdapter to allow this EventHandlerInvoker to correctly pass EventMessages to it.

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

eventHandlers

public SimpleEventHandlerInvoker.Builder eventHandlers(Object... eventHandlers)

Sets the eventHandlers this EventHandlerInvoker will forward all its events to. If an event handler is assignable to EventMessageHandler it will registered as is. If not, it will be wrapped by a new AnnotationEventHandlerAdapter.

Parameters:

eventHandlers - an array of Objects which can handle events

Returns:

the current Builder instance, for fluent interfacing

eventHandlers

public SimpleEventHandlerInvoker.Builder eventHandlers(List<?> eventHandlers)

Sets the eventHandlers this EventHandlerInvoker will forward all its events to. If an event handler is assignable to EventMessageHandler it will registered as is. If not, it will be wrapped by a new AnnotationEventHandlerAdapter.

Parameters:

eventHandlers - a List of Objects which can handle events

Returns:

the current Builder instance, for fluent interfacing

parameterResolverFactory

public SimpleEventHandlerInvoker.Builder parameterResolverFactory(ParameterResolverFactory parameterResolverFactory)

Sets the ParameterResolverFactory used to resolve parameter values for annotated handlers in the AnnotationEventHandlerAdapter this EventHandlerInvoker instantiates. This invoker will only instantiate a new EventMessageHandler if a given Event Handler (through eventHandlers(Object...) or eventHandlers(List)) is not assignable to EventMessageHandler.

Parameters:

parameterResolverFactory - the ParameterResolverFactory used to resolve parameter values for instantiated AnnotationEventHandlerAdapters

Returns:

the current Builder instance, for fluent interfacing

handlerDefinition

public SimpleEventHandlerInvoker.Builder handlerDefinition(HandlerDefinition handlerDefinition)

Sets the HandlerDefinition used to create concrete handlers in the annotated handlers in the AnnotationEventHandlerAdapter this EventHandlerInvoker instantiates. This invoker will only instantiate a new EventMessageHandler if a given Event Handler (through eventHandlers(Object...) or eventHandlers(List)) is not assignable to EventMessageHandler.

Parameters:

handlerDefinition - the HandlerDefinition used to create concrete handlers in the instantiated AnnotationEventHandlerAdapters

Returns:

the current Builder instance, for fluent interfacing

listenerInvocationErrorHandler

public SimpleEventHandlerInvoker.Builder listenerInvocationErrorHandler(ListenerInvocationErrorHandler listenerInvocationErrorHandler)

Sets the ListenerInvocationErrorHandler which deals with any Exceptions being thrown by the EventListeners. Defaults to a LoggingErrorHandler.

Parameters:

listenerInvocationErrorHandler - a ListenerInvocationErrorHandler which deals with any Exceptions being thrown by the EventListeners

Returns:

the current Builder instance, for fluent interfacing

sequencingPolicy

public SimpleEventHandlerInvoker.Builder sequencingPolicy(SequencingPolicy<? super EventMessage<?>> sequencingPolicy)

Sets the SequencingPolicy in charge of deciding whether a given event should be handled (through SimpleEventHandlerInvoker.handle(EventMessage, Segment)) by the given Segment. Used when this EventHandlerInvoker is invoked for multiple Segments (i.e. using parallel processing). Defaults to a SequentialPerAggregatePolicy,

Parameters:

sequencingPolicy - a SequencingPolicy in charge of deciding whether a given event should be handled by the given Segment

Returns:

the current Builder instance, for fluent interfacing

build

public SimpleEventHandlerInvoker build()

Initializes a SimpleEventHandlerInvoker as specified through this Builder.

Returns:

a SimpleEventHandlerInvoker as specified through this Builder

wrapEventMessageHandler

public AnnotationEventHandlerAdapter wrapEventMessageHandler(Object eventHandler)

Wrap a given eventHandler in an AnnotationEventHandlerAdapter to allow this EventHandlerInvoker to correctly pass EventMessages to it. If a ParameterResolverFactory or both a ParameterResolverFactory and HandlerDefinition are present, one/both will be given to the AnnotationEventHandlerAdapter

Parameters:

eventHandler - an Object which will be wrapped in an AnnotationEventHandlerAdapter

Returns:

an AnnotationEventHandlerAdapter which the given eventHandler will be wrapped in

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