ai.grakn.engine.tasks.manager.singlequeue

Class FailoverElector

java.lang.Object

org.apache.curator.framework.recipes.leader.LeaderSelectorListenerAdapter

ai.grakn.engine.tasks.manager.singlequeue.FailoverElector

All Implemented Interfaces:

org.apache.curator.framework.recipes.leader.LeaderSelectorListener, org.apache.curator.framework.state.ConnectionStateListener

public class FailoverElector
extends org.apache.curator.framework.recipes.leader.LeaderSelectorListenerAdapter

The FailoverElector it registers itself with the leadership election and controls the lifecycle of TaskFailover if elected

Author:

alexandraorth

Constructor Summary

Constructors

Constructor and Description
FailoverElector(EngineID identifier, ZookeeperConnection zookeeper, TaskStateStorage storage) Instantiating a FailoverElector adds this engine to the leadership selection process

Method Summary

Modifier and Type	Method and Description
EngineID	awaitLeader() Return the identifier of the current leader.
void	renounce()
void	takeLeadership(org.apache.curator.framework.CuratorFramework client) Called when this instance of TaskFailover is elected as leader and starts listening for failed engines.

Methods inherited from class org.apache.curator.framework.recipes.leader.LeaderSelectorListenerAdapter

stateChanged

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FailoverElector

public FailoverElector(EngineID identifier,
                       ZookeeperConnection zookeeper,
                       TaskStateStorage storage)

Instantiating a FailoverElector adds this engine to the leadership selection process

Method Detail

renounce

public void renounce()

awaitLeader

public EngineID awaitLeader()

Return the identifier of the current leader. Block until there is a leader.

takeLeadership

public void takeLeadership(org.apache.curator.framework.CuratorFramework client)
                    throws Exception

Called when this instance of TaskFailover is elected as leader and starts listening for failed engines.

Throws:

Exception