com.sun.sgs.impl.service.nodemap
Interface NodeMappingServer

All Superinterfaces:

Remote

All Known Implementing Classes:

NodeMappingServerImpl

interface NodeMappingServer
extends Remote

Defines the service interface for the global portion of the NodeMappingService.

Method Summary

boolean	assertValid(Identity identity) Check the validity of the data store for a particular identity.
long	assignNode(Class service, Identity id, long requestingNode) Assigns the identity to a node and indicates that the service class believes this identity is active.
void	canMove(Identity id) All IdentityRelocationListeners have completed their work, so it's safe to move the identity.
void	canRemove(Identity id) The identity's reference count has gone to zero, so it can be removed.
void	registerNodeListener(NotifyClient client, long nodeId) Register a NotifyClient object to be called when changes occur on a particular node.
void	unregisterNodeListener(long nodeId) Unregister the NotifyClient object for a node if one is registered.

Method Detail

assignNode

long assignNode(Class service,
                Identity id,
                long requestingNode)
                throws IOException

Assigns the identity to a node and indicates that the service class believes this identity is active. If the id has already been assigned to a node, simply return that assignment. If the id is assigned to a node that's not alive, reassign it.

Parameters:

service - the class of the calling service

id - the identity to assign should this be a set?

requestingNode - the id of the node requesting assignment

Returns:

the ID of the node that the identity was assigned to, or -1 if the assignment failed

Throws:

IOException - if a communication problem occurs while invoking this method

canRemove

void canRemove(Identity id)
               throws IOException

The identity's reference count has gone to zero, so it can be removed.

Parameters:

id - the identity which can be removed from the map

Throws:

IOException - if a communication problem occurs while invoking this method

canMove

void canMove(Identity id)
             throws IOException

All IdentityRelocationListeners have completed their work, so it's safe to move the identity.

Parameters:

id - the identity which can now be moved

Throws:

IOException - if a communication problem occurs while invoking this method

registerNodeListener

void registerNodeListener(NotifyClient client,
                          long nodeId)
                          throws IOException

Register a NotifyClient object to be called when changes occur on a particular node. Only one listener object can be registered per nodeId, and registering a listener will clear any previously registered listener for that nodeId.

Registration must only be made during service startup.

Parameters:

client - the callback client

nodeId - the node which client is interested in changes to

Throws:

IOException - if a communication problem occurs while invoking this method

unregisterNodeListener

void unregisterNodeListener(long nodeId)
                            throws IOException

Unregister the NotifyClient object for a node if one is registered.

Parameters:

nodeId - the node

Throws:

IOException - if a communication problem occurs while invoking this method

assertValid

boolean assertValid(Identity identity)
                    throws Exception

Check the validity of the data store for a particular identity. Used for testing.

Parameters:

identity - the identity

Returns:

true if all is well, false if there is a problem

Throws:

Exception - if any error occurs