com.iplanet.dpro.session.service.cluster

Interface ClusterMonitor

All Known Implementing Classes:

MultiServerClusterMonitor, SingleServerClusterMonitor

public interface ClusterMonitor

API for querying status of servers in cluster. Extracted from SessionService class as part of first-pass refactoring to improve SessionService adherence to SRP.

Since:

13.0.0

Method Summary

Modifier and Type	Method and Description
boolean	checkServerUp(String serverId) Indicates if the specified server is up.
String	getCurrentHostServer(SessionID sessionId) Identify the host (aka home or authoritative) server for the provided session.
boolean	isSiteUp(String siteId) Indicates if the specified site is up.
void	shutdown() Signals that the ClusterMonitor instance should shutdown.

Method Detail

isSiteUp

boolean isSiteUp(String siteId)

Indicates if the specified site is up.

Parameters:

siteId - A possibly null Site Id.

Returns:

True if the Site is up, False if it failed to respond to a query.

checkServerUp

boolean checkServerUp(String serverId)

Indicates if the specified server is up.

Parameters:

serverId - server id

Returns:

true if server is up, false otherwise

getCurrentHostServer

String getCurrentHostServer(SessionID sessionId)
                     throws SessionException

Identify the host (aka home or authoritative) server for the provided session. If the currently assigned host server for the session is found to be down, this method uses a deterministic algorithm to select a new one from those known to the clustering servive based on the session's STORAGE_KEY. This is the key method of "internal request routing".

Parameters:

sessionId - SessionID for which the home server is to be found

Returns:

server id for the server instance determined to be the current host

Throws:

SessionException

shutdown

void shutdown()

Signals that the ClusterMonitor instance should shutdown. Once called the instance will not receive any further calls.