software.chronicle.datagrid.pubsub

Interface Subscriber<E>

Type Parameters:

E - event type

All Superinterfaces:

BaseSubscriber, Consumer<E>, HasUsingMessage<E>

All Known Subinterfaces:

ConsumingSubscriber<E>, MapEntrySubscriber<K,V>

All Known Implementing Classes:

Filter.FilteredSubscriber, VanillaIndexAwareSubscriber, VanillaSubscriber

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Subscriber<E>
extends BaseSubscriber, Consumer<E>, HasUsingMessage<E>

Subscriber to events of a specific topic/key.

Waring: Subscribers cannot modify its underlying asset using the same thread that was used for calling the Subscriber. For example, a Subscriber to a MapView must not update the MapView itself in the same thread.

Method Summary

Modifier and Type	Method and Description
default void	accept(E e)
static <M> SubscriberBuilder<M>	builder(Class<M> messageClassToken) Creates and returns a new SubscriberBuilder that can be used to configure and build new Subscribers.
static <E> Subscriber<E>	indexAware(@NotNull Subscriber<E> subscriber) Ensures that the provided subscriber is index aware, if it is, returns the provided subscriber or else creates and returns a new Subscriber that wraps the provided subscriber and that implements the methods BaseSubscriber.index(), and BaseSubscriber.index(long).
default void	onEndOfBootStrap() This method is optionally invoked by Datagrid upon end of bootstrapping.
void	onMessage(E e) This method is invoked by DataGrid when there is a new unseen event.

Methods inherited from interface software.chronicle.datagrid.pubsub.BaseSubscriber

index, index, isIndexAware, isTcpBufferFullEnough, onEndOfSubscription

Methods inherited from interface java.util.function.Consumer

andThen

Methods inherited from interface software.chronicle.datagrid.pubsub.HasUsingMessage

usingMessage

Method Detail

onMessage

void onMessage(E e)
        throws InvalidSubscriberException

This method is invoked by DataGrid when there is a new unseen event.

Parameters:

e - event

Throws:

InvalidSubscriberException - is thrown if this subscriber is no longer valid.

accept

default void accept(E e)

Specified by:

accept in interface Consumer<E>

onEndOfBootStrap

default void onEndOfBootStrap()

This method is optionally invoked by Datagrid upon end of bootstrapping.

Currently, only a TopologySubscription support this call-back.

indexAware

static <E> Subscriber<E> indexAware(@NotNull
                                    @NotNull Subscriber<E> subscriber)

Ensures that the provided subscriber is index aware, if it is, returns the provided subscriber or else creates and returns a new Subscriber that wraps the provided subscriber and that implements the methods BaseSubscriber.index(), and BaseSubscriber.index(long).

An index aware TopicSubscriber keeps track of its last known index, allowing a subscriber to be seamlessly handed over between servers.

Type Parameters:

E - message type

Parameters:

subscriber - to wrap

Returns:

a new Subscriber that wraps the provided topicSubscriber and that implements the methods BaseSubscriber.index(), and BaseSubscriber.index(long)

builder

static <M> SubscriberBuilder<M> builder(Class<M> messageClassToken)

Creates and returns a new SubscriberBuilder that can be used to configure and build new Subscribers.

Type Parameters:

M - message type

Parameters:

messageClassToken - representing the message type

Returns:

a new SubscriberBuilder that can be used to configure and build new Subscribers