org.apache.hedwig.client.api

Interface Subscriber

public interface Subscriber

Interface to define the client Subscriber API.

Method Summary

Methods

Modifier and Type	Method and Description
void	asyncCloseSubscription(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, Callback<Void> callback, Object context) Closes all of the client side cached data for this subscription without actually sending an unsubscribe request to the server.
void	asyncSubscribe(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, PubSubProtocol.SubscribeRequest.CreateOrAttach mode, Callback<Void> callback, Object context) Subscribe to the given topic asynchronously for the inputted subscriberId disregarding if the topic has been created yet or not.
void	asyncUnsubscribe(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, Callback<Void> callback, Object context) Unsubscribe from a topic asynchronously that the subscriberId user has previously subscribed to.
void	closeSubscription(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId) Closes all of the client side cached data for this subscription without actually sending an unsubscribe request to the server.
void	consume(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, PubSubProtocol.MessageSeqId messageSeqId) Manually send a consume message to the server for the given inputs.
List<com.google.protobuf.ByteString>	getSubscriptionList(com.google.protobuf.ByteString subscriberId) Fills the input List with the subscriptions this subscriberId client is subscribed to.
boolean	hasSubscription(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId) Checks if the subscriberId client is currently subscribed to the given topic.
void	startDelivery(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, MessageHandler messageHandler) Begin delivery of messages from the server to us for this topic and subscriberId.
void	stopDelivery(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId) Stop delivery of messages for this topic and subscriberId.
void	subscribe(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId, PubSubProtocol.SubscribeRequest.CreateOrAttach mode) Subscribe to the given topic for the inputted subscriberId.
void	unsubscribe(com.google.protobuf.ByteString topic, com.google.protobuf.ByteString subscriberId) Unsubscribe from a topic that the subscriberId user has previously subscribed to.

Method Detail

subscribe

void subscribe(com.google.protobuf.ByteString topic,
             com.google.protobuf.ByteString subscriberId,
             PubSubProtocol.SubscribeRequest.CreateOrAttach mode)
               throws PubSubException.CouldNotConnectException,
                      PubSubException.ClientAlreadySubscribedException,
                      PubSubException.ServiceDownException,
                      org.apache.hedwig.client.exceptions.InvalidSubscriberIdException

Subscribe to the given topic for the inputted subscriberId.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

mode - Whether to prohibit, tolerate, or require an existing subscription.

Throws:

PubSubException.CouldNotConnectException - If we are not able to connect to the server host

PubSubException.ClientAlreadySubscribedException - If client is already subscribed to the topic

PubSubException.ServiceDownException - If unable to subscribe to topic

org.apache.hedwig.client.exceptions.InvalidSubscriberIdException - If the subscriberId is not valid. We may want to set aside certain formats of subscriberId's for different purposes. e.g. local vs. hub subscriber

asyncSubscribe

void asyncSubscribe(com.google.protobuf.ByteString topic,
                  com.google.protobuf.ByteString subscriberId,
                  PubSubProtocol.SubscribeRequest.CreateOrAttach mode,
                  Callback<Void> callback,
                  Object context)

Subscribe to the given topic asynchronously for the inputted subscriberId disregarding if the topic has been created yet or not.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

mode - Whether to prohibit, tolerate, or require an existing subscription.

callback - Callback to invoke when the subscribe request to the server has actually gone through. This will have to deal with error conditions on the async subscribe request.

context - Calling context that the Callback needs since this is done asynchronously.

unsubscribe

void unsubscribe(com.google.protobuf.ByteString topic,
               com.google.protobuf.ByteString subscriberId)
                 throws PubSubException.CouldNotConnectException,
                        PubSubException.ClientNotSubscribedException,
                        PubSubException.ServiceDownException,
                        org.apache.hedwig.client.exceptions.InvalidSubscriberIdException

Unsubscribe from a topic that the subscriberId user has previously subscribed to.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

Throws:

PubSubException.CouldNotConnectException - If we are not able to connect to the server host

PubSubException.ClientNotSubscribedException - If the client is not currently subscribed to the topic

PubSubException.ServiceDownException - If the server was down and unable to complete the request

org.apache.hedwig.client.exceptions.InvalidSubscriberIdException - If the subscriberId is not valid. We may want to set aside certain formats of subscriberId's for different purposes. e.g. local vs. hub subscriber

asyncUnsubscribe

void asyncUnsubscribe(com.google.protobuf.ByteString topic,
                    com.google.protobuf.ByteString subscriberId,
                    Callback<Void> callback,
                    Object context)

Unsubscribe from a topic asynchronously that the subscriberId user has previously subscribed to.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

callback - Callback to invoke when the unsubscribe request to the server has actually gone through. This will have to deal with error conditions on the async unsubscribe request.

context - Calling context that the Callback needs since this is done asynchronously.

consume

void consume(com.google.protobuf.ByteString topic,
           com.google.protobuf.ByteString subscriberId,
           PubSubProtocol.MessageSeqId messageSeqId)
             throws PubSubException.ClientNotSubscribedException

Manually send a consume message to the server for the given inputs.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

messageSeqId - Message Sequence ID for the latest message that the client app has successfully consumed. All messages up to that point will also be considered as consumed.

Throws:

PubSubException.ClientNotSubscribedException - If the client is not currently subscribed to the topic based on the client's local state.

hasSubscription

boolean hasSubscription(com.google.protobuf.ByteString topic,
                      com.google.protobuf.ByteString subscriberId)
                        throws PubSubException.CouldNotConnectException,
                               PubSubException.ServiceDownException

Checks if the subscriberId client is currently subscribed to the given topic.

Parameters:

topic - Topic name of the subscription.

subscriberId - ID of the subscriber

Returns:

Boolean indicating if the client has a subscription or not.

Throws:

PubSubException.CouldNotConnectException - If we are not able to connect to the server host

PubSubException.ServiceDownException - If there is an error checking the server if the client has a subscription

getSubscriptionList

List<com.google.protobuf.ByteString> getSubscriptionList(com.google.protobuf.ByteString subscriberId)
                                                         throws PubSubException.CouldNotConnectException,
                                                                PubSubException.ServiceDownException

Fills the input List with the subscriptions this subscriberId client is subscribed to.

Parameters:

subscriberId - ID of the subscriber

Returns:

List filled with subscription name (topic) strings.

Throws:

PubSubException.CouldNotConnectException - If we are not able to connect to the server host

PubSubException.ServiceDownException - If there is an error retrieving the list of topics

startDelivery

void startDelivery(com.google.protobuf.ByteString topic,
                 com.google.protobuf.ByteString subscriberId,
                 MessageHandler messageHandler)
                   throws PubSubException.ClientNotSubscribedException

Begin delivery of messages from the server to us for this topic and subscriberId.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

messageHandler - Message Handler that will consume the subscribed messages

Throws:

PubSubException.ClientNotSubscribedException - If the client is not currently subscribed to the topic

stopDelivery

void stopDelivery(com.google.protobuf.ByteString topic,
                com.google.protobuf.ByteString subscriberId)
                  throws PubSubException.ClientNotSubscribedException

Stop delivery of messages for this topic and subscriberId.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

Throws:

PubSubException.ClientNotSubscribedException - If the client is not currently subscribed to the topic

closeSubscription

void closeSubscription(com.google.protobuf.ByteString topic,
                     com.google.protobuf.ByteString subscriberId)
                       throws PubSubException.ServiceDownException

Closes all of the client side cached data for this subscription without actually sending an unsubscribe request to the server. This will close the subscribe channel synchronously (if it exists) for the topic.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

Throws:

PubSubException.ServiceDownException - If the subscribe channel was not able to be closed successfully

asyncCloseSubscription

void asyncCloseSubscription(com.google.protobuf.ByteString topic,
                          com.google.protobuf.ByteString subscriberId,
                          Callback<Void> callback,
                          Object context)

Closes all of the client side cached data for this subscription without actually sending an unsubscribe request to the server. This will close the subscribe channel asynchronously (if it exists) for the topic.

Parameters:

topic - Topic name of the subscription

subscriberId - ID of the subscriber

callback - Callback to invoke when the subscribe channel has been closed.

context - Calling context that the Callback needs since this is done asynchronously.