Package 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

    • 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> Future<Message<T>> request​(String address,
                                       Object message)
        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
        Returns:
        a future notified when any reply from the recipient is received

      • request

        <T> Future<Message<T>> request​(String address,
                               Object message,
                               DeliveryOptions options)
        Like request(String, Object) 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
        Returns:
        a future notified when any reply from the recipient is received

      • 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

      • 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

      • 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

      • 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