org.apache.cassandra.gms
Interface IFailureDetector

All Known Implementing Classes:
FailureDetector

public interface IFailureDetector

An interface that provides an application with the ability to query liveness information of a node in the cluster. It also exposes methods which help an application register callbacks for notifications of liveness information of nodes.


Method Summary
 void interpret(EndPoint ep)
          This method is invoked by any entity wanting to interrogate the status of an endpoint.
 boolean isAlive(EndPoint ep)
          Failure Detector's knowledge of whether a node is up or down.
 void registerFailureDetectionEventListener(IFailureDetectionEventListener listener)
          Register interest for Failure Detector events.
 void report(EndPoint ep)
          This method is invoked by the receiver of the heartbeat.
 void unregisterFailureDetectionEventListener(IFailureDetectionEventListener listener)
          Un-register interest for Failure Detector events.
 

Method Detail

isAlive

boolean isAlive(EndPoint ep)
Failure Detector's knowledge of whether a node is up or down.

Parameters:
ep - endpoint in question.
Returns:
true if UP and false if DOWN.

interpret

void interpret(EndPoint ep)
This method is invoked by any entity wanting to interrogate the status of an endpoint. In our case it would be the Gossiper. The Failure Detector will then calculate Phi and deem an endpoint as suspicious or alive as explained in the Hayashibara paper. param ep endpoint for which we interpret the inter arrival times.


report

void report(EndPoint ep)
This method is invoked by the receiver of the heartbeat. In our case it would be the Gossiper. Gossiper inform the Failure Detector on receipt of a heartbeat. The FailureDetector will then sample the arrival time as explained in the paper. param ep endpoint being reported.


registerFailureDetectionEventListener

void registerFailureDetectionEventListener(IFailureDetectionEventListener listener)
Register interest for Failure Detector events.

Parameters:
listener - implementation of an application provided IFailureDetectionEventListener

unregisterFailureDetectionEventListener

void unregisterFailureDetectionEventListener(IFailureDetectionEventListener listener)
Un-register interest for Failure Detector events.

Parameters:
listener - implementation of an application provided IFailureDetectionEventListener


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