com.rabbitmq.client

Interface Consumer

All Known Subinterfaces:

RpcServer.RpcConsumer

All Known Implementing Classes:

DefaultConsumer

public interface Consumer

Interface for application callback objects to receive notifications and messages from a queue by subscription. Most implementations will subclass DefaultConsumer.

The methods of this interface are invoked in a dispatch thread which is separate from the Connection's thread. This allows Consumers to call Channel or Connection methods without causing a deadlock.

The Consumers on a particular Channel are invoked serially on one or more dispatch threads. Consumers should avoid executing long-running code because this will delay dispatch of messages to other Consumers on the same Channel. For a lambda-oriented syntax, use DeliverCallback, CancelCallback, and ConsumerShutdownSignalCallback.

See Also:

Channel.basicConsume(String, boolean, String, boolean, boolean, java.util.Map, Consumer), Channel.basicCancel(java.lang.String)

Method Summary

Modifier and Type	Method and Description
void	handleCancel(String consumerTag) Called when the consumer is cancelled for reasons other than by a call to Channel.basicCancel(java.lang.String).
void	handleCancelOk(String consumerTag) Called when the consumer is cancelled by a call to Channel.basicCancel(java.lang.String).
void	handleConsumeOk(String consumerTag) Called when the consumer is registered by a call to any of the Channel.basicConsume(java.lang.String, com.rabbitmq.client.Consumer) methods.
void	handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) Called when a basic.deliver is received for this consumer.
void	handleRecoverOk(String consumerTag) Called when a basic.recover-ok is received in reply to a basic.recover.
void	handleShutdownSignal(String consumerTag, ShutdownSignalException sig) Called when either the channel or the underlying connection has been shut down.

Method Detail

handleConsumeOk

void handleConsumeOk(String consumerTag)

Called when the consumer is registered by a call to any of the Channel.basicConsume(java.lang.String, com.rabbitmq.client.Consumer) methods.

Parameters:

consumerTag - the consumer tag associated with the consumer

handleCancelOk

void handleCancelOk(String consumerTag)

Called when the consumer is cancelled by a call to Channel.basicCancel(java.lang.String).

Parameters:

consumerTag - the consumer tag associated with the consumer

handleCancel

void handleCancel(String consumerTag)
           throws IOException

Called when the consumer is cancelled for reasons other than by a call to Channel.basicCancel(java.lang.String). For example, the queue has been deleted. See handleCancelOk(java.lang.String) for notification of consumer cancellation due to Channel.basicCancel(java.lang.String).

Parameters:

consumerTag - the consumer tag associated with the consumer

Throws:

IOException

handleShutdownSignal

void handleShutdownSignal(String consumerTag,
                          ShutdownSignalException sig)

Called when either the channel or the underlying connection has been shut down.

Parameters:

consumerTag - the consumer tag associated with the consumer

sig - a ShutdownSignalException indicating the reason for the shut down

handleRecoverOk

void handleRecoverOk(String consumerTag)

Called when a basic.recover-ok is received in reply to a basic.recover. All messages received before this is invoked that haven't been ack'ed will be re-delivered. All messages received afterwards won't be.

Parameters:

consumerTag - the consumer tag associated with the consumer

handleDelivery

void handleDelivery(String consumerTag,
                    Envelope envelope,
                    AMQP.BasicProperties properties,
                    byte[] body)
             throws IOException

Called when a basic.deliver is received for this consumer.

Parameters:

consumerTag - the consumer tag associated with the consumer

envelope - packaging data for the message

properties - content header data for the message

body - the message body (opaque, client-specific byte array)

Throws:

IOException - if the consumer encounters an I/O error while processing the message

See Also:

Envelope