org.apache.flink.runtime.heartbeat

Interface HeartbeatListener<I,O>

Type Parameters:

I - Type of the incoming payload

O - Type of the outgoing payload

public interface HeartbeatListener<I,O>

Interface for the interaction with the HeartbeatManager. The heartbeat listener is used for the following things:

• Notifications about heartbeat timeouts
• Payload reports of incoming heartbeats
• Retrieval of payloads for outgoing heartbeats

Method Summary

Modifier and Type	Method and Description
void	notifyHeartbeatTimeout(ResourceID resourceID) Callback which is called if a heartbeat for the machine identified by the given resource ID times out.
void	reportPayload(ResourceID resourceID, I payload) Callback which is called whenever a heartbeat with an associated payload is received.
CompletableFuture<O>	retrievePayload(ResourceID resourceID) Retrieves the payload value for the next heartbeat message.

Method Detail

notifyHeartbeatTimeout

void notifyHeartbeatTimeout(ResourceID resourceID)

Callback which is called if a heartbeat for the machine identified by the given resource ID times out.

Parameters:

resourceID - Resource ID of the machine whose heartbeat has timed out

reportPayload

void reportPayload(ResourceID resourceID,
                   I payload)

Callback which is called whenever a heartbeat with an associated payload is received. The carried payload is given to this method.

Parameters:

resourceID - Resource ID identifying the sender of the payload

payload - Payload of the received heartbeat

retrievePayload

CompletableFuture<O> retrievePayload(ResourceID resourceID)

Retrieves the payload value for the next heartbeat message. Since the operation can happen asynchronously, the result is returned wrapped in a future.

Parameters:

resourceID - Resource ID identifying the receiver of the payload

Returns:

Future containing the next payload for heartbeats