org.hibernate.search.backend.jgroups.impl

Class SlaveNodeSelector

java.lang.Object

org.hibernate.search.backend.jgroups.impl.SlaveNodeSelector

All Implemented Interfaces:

NodeSelectorStrategy

public class SlaveNodeSelector
extends Object
implements NodeSelectorStrategy

This NodeSelectorStrategy is a static configuration for the local node to avoid processing any indexing operations locally. It is assumed that some other node in the cluster will process it; which node exactly is unknown, so messages are broadcasted to the group.

There is no guarantee of processing: if no master picks up the task, the index update operation is skipped. This can be mitigated by making sure at least one master is always online; if a persistent queue is needed it's better to use the JMS backend.

This implementation matches the jgroupsSlave configuration property.

Author:

Sanne Grinovero (C) 2012 Red Hat Inc.

Constructor Summary

Constructors

Constructor and Description
SlaveNodeSelector()

Method Summary

Modifier and Type	Method and Description
Message	createMessage(byte[] data) Different message options can be applied using different constructors, hence we delegate Message construction to the strategy.
boolean	isIndexOwnerLocal() Specifies if the current (local) node should apply changes to the index.
void	setLocalAddress(Address address) The implementation might need to know it's own address, so this is provided at channel initial connection.
void	viewAccepted(View view) Invoked by JGroups on view change.

Methods inherited from class java.lang.Object

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

Constructor Detail

SlaveNodeSelector

public SlaveNodeSelector()

Method Detail

isIndexOwnerLocal

public boolean isIndexOwnerLocal()

Description copied from interface: NodeSelectorStrategy

Specifies if the current (local) node should apply changes to the index.

Specified by:

isIndexOwnerLocal in interface NodeSelectorStrategy

Returns:

true if the local node is the owner

setLocalAddress

public void setLocalAddress(Address address)

Description copied from interface: NodeSelectorStrategy

The implementation might need to know it's own address, so this is provided at channel initial connection.

Specified by:

setLocalAddress in interface NodeSelectorStrategy

Parameters:

address - the local address

viewAccepted

public void viewAccepted(View view)

Description copied from interface: NodeSelectorStrategy

Invoked by JGroups on view change. MembershipListener.viewAccepted(View)

Specified by:

viewAccepted in interface NodeSelectorStrategy

Parameters:

view - contains information on the current members of the cluster group

createMessage

public Message createMessage(byte[] data)

Description copied from interface: NodeSelectorStrategy

Different message options can be applied using different constructors, hence we delegate Message construction to the strategy.

Specified by:

createMessage in interface NodeSelectorStrategy

Parameters:

data - the information to be sent to the master.

Returns:

the message to be sent.