org.springframework.integration.leader

Class AbstractCandidate

java.lang.Object

org.springframework.integration.leader.AbstractCandidate

All Implemented Interfaces:

Candidate

Direct Known Subclasses:

DefaultCandidate

public abstract class AbstractCandidate
extends Object
implements Candidate

Base implementation of a Candidate.

Author:

Janne Valkealahti, Gary Russell

Constructor Summary

Constructors

Constructor and Description
AbstractCandidate() Instantiate a abstract candidate.
AbstractCandidate(String id, String role) Instantiate a abstract candidate.

Method Summary

Modifier and Type	Method and Description
String	getId() Gets the identifier.
String	getRole() Gets the role.
abstract void	onGranted(Context ctx) Callback method invoked when this candidate is elected leader.
abstract void	onRevoked(Context ctx) Callback method invoked when this candidate is no longer leader.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractCandidate

public AbstractCandidate()

Instantiate a abstract candidate.

AbstractCandidate

public AbstractCandidate(@Nullable
                         String id,
                         @Nullable
                         String role)

Instantiate a abstract candidate.

Parameters:

id - the identifier

role - the role

Method Detail

getRole

public String getRole()

Description copied from interface: Candidate

Gets the role.

Specified by:

getRole in interface Candidate

Returns:

a string indicating the name of the leadership role this candidate is participating in; other candidates present in the system with the same name will contend for leadership

getId

public String getId()

Description copied from interface: Candidate

Gets the identifier.

Specified by:

getId in interface Candidate

Returns:

a unique ID for this candidate; no other candidate for leader election should return the same id

onGranted

public abstract void onGranted(Context ctx)
                        throws InterruptedException

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

Parameters:

ctx - leadership context

Throws:

InterruptedException - when this candidate is no longer leader

onRevoked

public abstract 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

Parameters:

ctx - leadership context