hazelcast::client::reliable_topic Class Reference

Hazelcast provides distribution mechanism for publishing messages that are delivered to multiple subscribers which is also known as publish/subscribe (pub/sub) messaging model. More...

#include <reliable_topic.h>

Inheritance diagram for hazelcast::client::reliable_topic:

Public Member Functions
template<typename E >
boost::future< void >	publish (const E &message)
	Publishes the message to all subscribers of this topic Current implementation only supports DISCARD_OLDEST policy as in Java client. More...
template<typename Listener >
std::string	add_message_listener (Listener &&listener)
	Subscribes to this topic. More...
bool	remove_message_listener (const std::string &registration_id)
	Stops receiving messages for the given message listener. More...

Static Public Attributes
static constexpr const char *	SERVICE_NAME = "hz:impl:reliableTopicService"

Protected Member Functions
void	on_shutdown () override
void	on_destroy () override
void	post_destroy () override

Friends
class	spi::ProxyManager
class	hazelcast_client

Detailed Description

Hazelcast provides distribution mechanism for publishing messages that are delivered to multiple subscribers which is also known as publish/subscribe (pub/sub) messaging model.

Publish and subscriptions are cluster-wide. When a member subscribes for a topic, it is actually registering for messages published by any member in the cluster, including the new members joined after you added the listener.

Messages are ordered, meaning, listeners(subscribers) will process the messages in the order they are actually published. If cluster member M publishes messages m1, m2, m3...mn to a topic T, then Hazelcast makes sure that all of the subscribers of topic T will receive and process m1, m2, m3...mn in order.

Definition at line 49 of file reliable_topic.h.

Member Function Documentation

add_message_listener()

template<typename Listener >

std::string hazelcast::client::reliable_topic::add_message_listener ( Listener &&  listener )

inline

Subscribes to this topic.

When someone publishes a message on this topic. onMessage() function of the given MessageListener is called. More than one message listener can be added on one instance.

Warning 1: If listener should do a time consuming operation, off-load the operation to another thread. otherwise it will slow down the system.

Warning 2: Do not make a call to hazelcast. It can cause deadlock.

Warning 3: Make sure that the MessageListener object is not destroyed until the removeListener is called, since the library will use the MessageListener reference to deliver incoming messages.

Parameters

listener

the MessageListener to add.

Returns

returns registration id.

Definition at line 87 of file reliable_topic.h.

                                                                {
                int id = ++runner_counter_;
                std::shared_ptr<MessageRunner < Listener>>
                runner(new MessageRunner<Listener>(id, std::forward<Listener>(listener), ringbuffer_.get(), get_name(),
                                                   get_serialization_service(), batch_size_, logger_, executor_,
                                                   runners_map_));
                runners_map_.put(id, runner);
                runner->next();
                return std::to_string(id);
            }

publish()

template<typename E >

boost::future<void> hazelcast::client::reliable_topic::publish ( const E &  message )

inline

Publishes the message to all subscribers of this topic Current implementation only supports DISCARD_OLDEST policy as in Java client.

The other policies will be available when async API is completed. Using this policy the oldest item is overwritten no matter it is not old enough to retire.

Parameters

message

The message to be published

Definition at line 64 of file reliable_topic.h.

                                                        {
                topic::impl::reliable::ReliableTopicMessage reliable_message(to_data(message), nullptr);
                return to_void_future(ringbuffer_.get()->add(reliable_message));
            }

remove_message_listener()

bool hazelcast::client::reliable_topic::remove_message_listener

(

const std::string &

registration_id

)

Stops receiving messages for the given message listener.

If the given listener already removed, this method does nothing.

Parameters

registrationId

Id of listener registration.

Returns

true if registration is removed, false otherwise

Definition at line 69 of file proxy.cpp.

                                                                                     {
            int id = util::IOUtil::to_value<int>(registration_id);
            auto runner = runners_map_.get(id);
            if (!runner) {
                return false;
            }
            runner->cancel();
            return true;
        }

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The documentation for this class was generated from the following files:

• hazelcast/include/hazelcast/client/reliable_topic.h
• hazelcast/src/hazelcast/client/proxy.cpp