io.vertx.core.eventbus

Interface EventBus

All Superinterfaces:

Measured

public interface EventBus
extends Measured

A Vert.x event-bus is a light-weight distributed messaging system which allows different parts of your application, or different applications and services to communicate with each in a loosely coupled way.

An event-bus supports publish-subscribe messaging, point-to-point messaging and request-response messaging.

Message delivery is best-effort and messages can be lost if failure of all or part of the event bus occurs.

Please refer to the documentation for more information on the event bus.

Author:

Tim Fox

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.function.Function<String,Boolean>	DEFAULT_SERIALIZABLE_CHECKER Default Serializable class checker used by Vert.x when serializableChecker(Function) has not been set.

Method Summary

Modifier and Type	Method and Description
<T> EventBus	addInboundInterceptor(Handler<DeliveryContext<T>> interceptor) Add an interceptor that will be called whenever a message is received by Vert.x
<T> EventBus	addOutboundInterceptor(Handler<DeliveryContext<T>> interceptor) Add an interceptor that will be called whenever a message is sent from Vert.x
EventBus	clusterSerializableChecker(java.util.function.Function<String,Boolean> classNamePredicate) Register a predicate to invoke when verifying if an object is forbidden to be encoded/decoded as ClusterSerializable.
EventBus	codecSelector(java.util.function.Function<Object,String> selector) Set selector to be invoked when the bus has not found any codec for a Message body.
<T> MessageConsumer<T>	consumer(String address) Create a message consumer against the specified address.
<T> MessageConsumer<T>	consumer(String address, Handler<Message<T>> handler) Create a consumer and register it against the specified address.
<T> MessageConsumer<T>	localConsumer(String address) Like consumer(String) but the address won't be propagated across the cluster.
<T> MessageConsumer<T>	localConsumer(String address, Handler<Message<T>> handler) Like consumer(String, Handler) but the address won't be propagated across the cluster.
EventBus	publish(String address, Object message) Publish a message.
EventBus	publish(String address, Object message, DeliveryOptions options) Like publish(String, Object) but specifying options that can be used to configure the delivery.
<T> MessageProducer<T>	publisher(String address) Create a message publisher against the specified address.
<T> MessageProducer<T>	publisher(String address, DeliveryOptions options) Like publisher(String) but specifying delivery options that will be used for configuring the delivery of the message.
EventBus	registerCodec(MessageCodec codec) Register a message codec.
<T> EventBus	registerDefaultCodec(Class<T> clazz, MessageCodec<T,?> codec) Register a default message codec.
<T> EventBus	removeInboundInterceptor(Handler<DeliveryContext<T>> interceptor) Remove an interceptor that was added by addInboundInterceptor(Handler)
<T> EventBus	removeOutboundInterceptor(Handler<DeliveryContext<T>> interceptor) Remove an interceptor that was added by addOutboundInterceptor(Handler)
default <T> Future<Message<T>>	request(String address, Object message) Like request(String, Object, Handler) but returns a Future of the asynchronous result
<T> Future<Message<T>>	request(String address, Object message, DeliveryOptions options) Like request(String, Object, DeliveryOptions, Handler) but returns a Future of the asynchronous result
default <T> EventBus	request(String address, Object message, DeliveryOptions options, Handler<AsyncResult<Message<T>>> replyHandler) Like request(String, Object, Handler) but specifying options that can be used to configure the delivery.
default <T> EventBus	request(String address, Object message, Handler<AsyncResult<Message<T>>> replyHandler) Sends a message and specify a replyHandler that will be called if the recipient subsequently replies to the message.
EventBus	send(String address, Object message) Sends a message.
EventBus	send(String address, Object message, DeliveryOptions options) Like send(String, Object) but specifying options that can be used to configure the delivery.
<T> MessageProducer<T>	sender(String address) Create a message sender against the specified address.
<T> MessageProducer<T>	sender(String address, DeliveryOptions options) Like sender(String) but specifying delivery options that will be used for configuring the delivery of the message.
EventBus	serializableChecker(java.util.function.Function<String,Boolean> classNamePredicate) Register a predicate to invoke when verifying if an object is allowed to be encoded/decoded as Serializable.
EventBus	unregisterCodec(String name) Unregister a message codec.
EventBus	unregisterDefaultCodec(Class clazz) Unregister a default message codec.

Methods inherited from interface io.vertx.core.metrics.Measured

isMetricsEnabled

Field Detail

DEFAULT_SERIALIZABLE_CHECKER

static final java.util.function.Function<String,Boolean> DEFAULT_SERIALIZABLE_CHECKER

Default Serializable class checker used by Vert.x when serializableChecker(Function) has not been set.

Method Detail

send

EventBus send(String address,
              Object message)

Sends a message.

The message will be delivered to at most one of the handlers registered to the address.

Parameters:

address - the address to send it to

message - the message, may be null

Returns:

a reference to this, so the API can be used fluently

send

EventBus send(String address,
              Object message,
              DeliveryOptions options)

Like send(String, Object) but specifying options that can be used to configure the delivery.

Parameters:

address - the address to send it to

message - the message, may be null

options - delivery options

Returns:

a reference to this, so the API can be used fluently

request

default <T> EventBus request(String address,
                             Object message,
                             Handler<AsyncResult<Message<T>>> replyHandler)

Sends a message and specify a replyHandler that will be called if the recipient subsequently replies to the message.

The message will be delivered to at most one of the handlers registered to the address.

Parameters:

address - the address to send it to

message - the message body, may be null

replyHandler - reply handler will be called when any reply from the recipient is received

Returns:

a reference to this, so the API can be used fluently

request

default <T> Future<Message<T>> request(String address,
                                       Object message)

Like request(String, Object, Handler) but returns a Future of the asynchronous result

request

default <T> EventBus request(String address,
                             Object message,
                             DeliveryOptions options,
                             Handler<AsyncResult<Message<T>>> replyHandler)

Like request(String, Object, Handler) but specifying options that can be used to configure the delivery.

Parameters:

address - the address to send it to

message - the message body, may be null

options - delivery options

replyHandler - reply handler will be called when any reply from the recipient is received

Returns:

a reference to this, so the API can be used fluently

request

<T> Future<Message<T>> request(String address,
                               Object message,
                               DeliveryOptions options)

Like request(String, Object, DeliveryOptions, Handler) but returns a Future of the asynchronous result

publish

EventBus publish(String address,
                 Object message)

Publish a message.

The message will be delivered to all handlers registered to the address.

Parameters:

address - the address to publish it to

message - the message, may be null

Returns:

a reference to this, so the API can be used fluently

publish

EventBus publish(String address,
                 Object message,
                 DeliveryOptions options)

Like publish(String, Object) but specifying options that can be used to configure the delivery.

Parameters:

address - the address to publish it to

message - the message, may be null

options - the delivery options

Returns:

a reference to this, so the API can be used fluently

consumer

<T> MessageConsumer<T> consumer(String address)

Create a message consumer against the specified address.

The returned consumer is not yet registered at the address, registration will be effective when MessageConsumer.handler(io.vertx.core.Handler) is called.

Parameters:

address - the address that it will register it at

Returns:

the event bus message consumer

consumer

<T> MessageConsumer<T> consumer(String address,
                                Handler<Message<T>> handler)

Create a consumer and register it against the specified address.

Parameters:

address - the address that will register it at

handler - the handler that will process the received messages

Returns:

the event bus message consumer

localConsumer

<T> MessageConsumer<T> localConsumer(String address)

Like consumer(String) but the address won't be propagated across the cluster.

Parameters:

address - the address to register it at

Returns:

the event bus message consumer

localConsumer

<T> MessageConsumer<T> localConsumer(String address,
                                     Handler<Message<T>> handler)

Like consumer(String, Handler) but the address won't be propagated across the cluster.

Parameters:

address - the address that will register it at

handler - the handler that will process the received messages

Returns:

the event bus message consumer

sender

<T> MessageProducer<T> sender(String address)

Create a message sender against the specified address.

The returned sender will invoke the send(String, Object) method when the stream WriteStream.write(Object) method is called with the sender address and the provided data.

Parameters:

address - the address to send it to

Returns:

The sender

sender

<T> MessageProducer<T> sender(String address,
                              DeliveryOptions options)

Like sender(String) but specifying delivery options that will be used for configuring the delivery of the message.

Parameters:

address - the address to send it to

options - the delivery options

Returns:

The sender

publisher

<T> MessageProducer<T> publisher(String address)

Create a message publisher against the specified address.

The returned publisher will invoke the publish(String, Object) method when the stream WriteStream.write(Object) method is called with the publisher address and the provided data.

Parameters:

address - The address to publish it to

Returns:

The publisher

publisher

<T> MessageProducer<T> publisher(String address,
                                 DeliveryOptions options)

Like publisher(String) but specifying delivery options that will be used for configuring the delivery of the message.

Parameters:

address - the address to publish it to

options - the delivery options

Returns:

The publisher

registerCodec

EventBus registerCodec(MessageCodec codec)

Register a message codec.

You can register a message codec if you want to send any non standard message across the event bus. E.g. you might want to send POJOs directly across the event bus.

To use a message codec for a send, you should specify it in the delivery options.

Parameters:

codec - the message codec to register

Returns:

a reference to this, so the API can be used fluently

unregisterCodec

EventBus unregisterCodec(String name)

Unregister a message codec.

Parameters:

name - the name of the codec

Returns:

a reference to this, so the API can be used fluently

registerDefaultCodec

<T> EventBus registerDefaultCodec(Class<T> clazz,
                                  MessageCodec<T,?> codec)

Register a default message codec.

You can register a message codec if you want to send any non standard message across the event bus. E.g. you might want to send POJOs directly across the event bus.

Default message codecs will be used to serialise any messages of the specified type on the event bus without the codec having to be specified in the delivery options.

Parameters:

clazz - the class for which to use this codec

codec - the message codec to register

Returns:

a reference to this, so the API can be used fluently

unregisterDefaultCodec

EventBus unregisterDefaultCodec(Class clazz)

Unregister a default message codec.

Parameters:

clazz - the class for which the codec was registered

Returns:

a reference to this, so the API can be used fluently

codecSelector

EventBus codecSelector(java.util.function.Function<Object,String> selector)

Set selector to be invoked when the bus has not found any codec for a Message body.

The selector must return the name of a codec which has been registered with either registerCodec(MessageCodec) or registerDefaultCodec(Class, MessageCodec).

Parameters:

selector - the codec selector

Returns:

a reference to this, so the API can be used fluently

addOutboundInterceptor

<T> EventBus addOutboundInterceptor(Handler<DeliveryContext<T>> interceptor)

Add an interceptor that will be called whenever a message is sent from Vert.x

Parameters:

interceptor - the interceptor

Returns:

a reference to this, so the API can be used fluently

removeOutboundInterceptor

<T> EventBus removeOutboundInterceptor(Handler<DeliveryContext<T>> interceptor)

Remove an interceptor that was added by addOutboundInterceptor(Handler)

Parameters:

interceptor - the interceptor

Returns:

a reference to this, so the API can be used fluently

addInboundInterceptor

<T> EventBus addInboundInterceptor(Handler<DeliveryContext<T>> interceptor)

Add an interceptor that will be called whenever a message is received by Vert.x

Parameters:

interceptor - the interceptor

Returns:

a reference to this, so the API can be used fluently

removeInboundInterceptor

<T> EventBus removeInboundInterceptor(Handler<DeliveryContext<T>> interceptor)

Remove an interceptor that was added by addInboundInterceptor(Handler)

Parameters:

interceptor - the interceptor

Returns:

a reference to this, so the API can be used fluently

clusterSerializableChecker

EventBus clusterSerializableChecker(java.util.function.Function<String,Boolean> classNamePredicate)

Register a predicate to invoke when verifying if an object is forbidden to be encoded/decoded as ClusterSerializable.

This is only used when Vert.x is clustered.

Parameters:

classNamePredicate - the predicate

Returns:

a reference to this, so the API can be used fluently

serializableChecker

EventBus serializableChecker(java.util.function.Function<String,Boolean> classNamePredicate)

Register a predicate to invoke when verifying if an object is allowed to be encoded/decoded as Serializable.

This is only used when Vert.x is clustered.

Parameters:

classNamePredicate - the predicate

Returns:

a reference to this, so the API can be used fluently