Package org.springframework.integration.leader

Class DefaultCandidate

java.lang.Object

org.springframework.integration.leader.AbstractCandidate

org.springframework.integration.leader.DefaultCandidate

All Implemented Interfaces:

Candidate

public class DefaultCandidate
extends AbstractCandidate

Simple Candidate for leadership. This implementation simply logs when it is elected and when its leadership is revoked.

Since:

4.2

Author:

Janne Valkealahti, Artem Bilan

Constructor Summary

Constructors

Constructor	Description
DefaultCandidate()	Instantiate a default candidate.
DefaultCandidate(String id, String role)	Instantiate a default candidate.

Method Summary

Modifier and Type	Method	Description
void	onGranted(Context ctx)	Callback method invoked when this candidate is elected leader.
void	onRevoked(Context ctx)	Callback method invoked when this candidate is no longer leader.
String	toString()
void	yieldLeadership()	Voluntarily yield leadership if held.

Methods inherited from class org.springframework.integration.leader.AbstractCandidate

getId, getRole

Methods inherited from class java.lang.Object

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

Constructor Details

DefaultCandidate

public DefaultCandidate()

Instantiate a default candidate.

DefaultCandidate

public DefaultCandidate(String id,
 String role)

Instantiate a default candidate.

Parameters:

id - the identifier

role - the role

Method Details

onGranted

public void onGranted(Context ctx)

Description copied from interface: Candidate

Callback method invoked when this candidate is elected leader. Implementations may chose to launch a background thread to perform leadership roles and return immediately. Another option is for implementations to perform all leadership work in the thread invoking this method. In the latter case, the method must respond to thread interrupts by throwing InterruptedException. When the thread is interrupted, this indicates that this candidate is no longer leader.

Specified by:

onGranted in interface Candidate

Specified by:

onGranted in class AbstractCandidate

Parameters:

ctx - leadership context

onRevoked

public void onRevoked(Context ctx)

Description copied from interface: Candidate

Callback method invoked when this candidate is no longer leader. Implementations should use this to shut down any resources (threads, network connections, etc) used to perform leadership work.

Specified by:

onRevoked in interface Candidate

Specified by:

onRevoked in class AbstractCandidate

Parameters:

ctx - leadership context

yieldLeadership

public void yieldLeadership()

Voluntarily yield leadership if held. If leader context is not yet known this method does nothing. Leader context becomes available only after onGranted(Context) method is called by the leader initiator.

toString

public String toString()

Overrides:

toString in class Object