io.atomix.core.election

Interface LeaderElection<T>

All Superinterfaces:

DistributedPrimitive, SyncPrimitive

public interface LeaderElection<T>
extends SyncPrimitive

LeaderElector provides the same functionality as AsyncLeaderElection with the only difference that all its methods block until the corresponding operation completes.

Field Summary

Fields inherited from interface io.atomix.primitive.DistributedPrimitive

DEFAULT_OPERATION_TIMEOUT_MILLIS

Method Summary

Modifier and Type	Method and Description
void	addListener(LeadershipEventListener<T> listener) Registers a listener to be notified of Leadership changes for all topics.
boolean	anoint(T identifier) Attempts to promote a node to leadership displacing the current leader.
AsyncLeaderElection<T>	async() Returns the underlying asynchronous primitive.
void	evict(T identifier) Attempts to evict a node from all leadership elections it is registered for.
Leadership<T>	getLeadership() Returns the Leadership for the specified topic.
boolean	promote(T identifier) Attempts to promote a node to top of candidate list.
void	removeListener(LeadershipEventListener<T> listener) Unregisters a previously registered change notification listener.
Leadership<T>	run(T identifier) Attempts to become leader for a topic.
void	withdraw(T identifier) Withdraws from leadership race for a topic.

Methods inherited from interface io.atomix.primitive.SyncPrimitive

close, delete

Methods inherited from interface io.atomix.primitive.DistributedPrimitive

addStateChangeListener, name, protocol, removeStateChangeListener, type

Method Detail

run

Leadership<T> run(T identifier)

Attempts to become leader for a topic.

Parameters:

identifier - candidate identifier

Returns:

current Leadership state of the topic

withdraw

void withdraw(T identifier)

Withdraws from leadership race for a topic.

Parameters:

identifier - identifier of the node to withdraw

anoint

boolean anoint(T identifier)

Attempts to promote a node to leadership displacing the current leader.

Parameters:

identifier - identifier of the new leader

Returns:

true if leadership transfer was successfully executed; false if it failed. This operation can return false if the node to be made new leader is not registered to run for election for the topic.

promote

boolean promote(T identifier)

Attempts to promote a node to top of candidate list.

Parameters:

identifier - identifier of the new top candidate

Returns:

true if node is now the top candidate. This operation can fail (i.e. return false) if the node is not registered to run for election for the topic.

evict

void evict(T identifier)

Attempts to evict a node from all leadership elections it is registered for.

If the node the current leader for a topic, this call will force the next candidate (if one exists) to be promoted to leadership.

Parameters:

identifier - identifier

getLeadership

Leadership<T> getLeadership()

Returns the Leadership for the specified topic.

Returns:

current Leadership state of the topic

addListener

void addListener(LeadershipEventListener<T> listener)

Registers a listener to be notified of Leadership changes for all topics.

Parameters:

listener - listener to add

removeListener

void removeListener(LeadershipEventListener<T> listener)

Unregisters a previously registered change notification listener.

If the specified listener was not previously registered, this operation will be a noop.

Parameters:

listener - listener to remove

async

AsyncLeaderElection<T> async()

Description copied from interface: SyncPrimitive

Returns the underlying asynchronous primitive.

Specified by:

async in interface SyncPrimitive

Returns:

the underlying asynchronous primitive