Package org.opennms.features.distributed.coordination.common

Class ConnectionBasedDomainManager

java.lang.Object

org.opennms.features.distributed.coordination.common.AbstractDomainManager

org.opennms.features.distributed.coordination.common.ConnectionBasedDomainManager

All Implemented Interfaces:

DomainManager

Direct Known Subclasses:

ZookeeperDomainManager

public abstract class ConnectionBasedDomainManager
extends AbstractDomainManager

A DomainManager that must connect to an external source before being able to participate in a leadership election.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ConnectionBasedDomainManager(String domain)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected abstract void	connect()	Implementations must connect via this method.
protected abstract void	disconnect()	Implementations must disconnect via this method.
protected void	failedToConnect(Throwable exception)	Implementations can optionally override this if they need special handling for a failure to connect.
boolean	isConnected()	Checks if this domain manager is connected.
protected void	onFirstRegister()	Implementations must handle any specific logic for dealing with a registration that adds to the map of handlers for the first time (such as connecting).
protected void	onLastDeregister()	Implementations must handle any specific logic for dealing with a deregistration that empties the map of handlers (such as disconnecting).
String	toString()

Methods inherited from class org.opennms.features.distributed.coordination.common.AbstractDomainManager

becomeActive, becomeStandby, deregister, getCurrentRole, getDomain, getRoleChangeHandlers, isAnythingRegistered, isRegistered, register

Methods inherited from class java.lang.Object

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

Constructor Detail

ConnectionBasedDomainManager

protected ConnectionBasedDomainManager(String domain)

Constructor.

Parameters:

domain - the domain to manage

Method Detail

isConnected

public boolean isConnected()

Checks if this domain manager is connected.

Returns:

true if connected, false otherwise

failedToConnect

protected void failedToConnect(Throwable exception)

Implementations can optionally override this if they need special handling for a failure to connect.

Parameters:

exception - the exception that caused the failure the connect

connect

protected abstract void connect()

Implementations must connect via this method.

This is executed in a separate thread so timeliness is not a factor. It is possible that multiple calls to connect() block waiting for the first one to finish so implementations of this method must be written to guard against this being a problem.

disconnect

protected abstract void disconnect()

Implementations must disconnect via this method.

This is executed in a separate thread so timeliness is not a factor. It is possible that multiple calls to disconnect() block waiting for the first one to finish so implementations of this method must be written to guard against this being a problem.

onFirstRegister

protected final void onFirstRegister()

Description copied from class: AbstractDomainManager

Implementations must handle any specific logic for dealing with a registration that adds to the map of handlers for the first time (such as connecting).

Specified by:

onFirstRegister in class AbstractDomainManager

onLastDeregister

protected final void onLastDeregister()

Description copied from class: AbstractDomainManager

Implementations must handle any specific logic for dealing with a deregistration that empties the map of handlers (such as disconnecting).

Specified by:

onLastDeregister in class AbstractDomainManager

toString

public String toString()

Overrides:

toString in class AbstractDomainManager