com.iplanet.dpro.session.service.cluster

Class MultiServerClusterMonitor

java.lang.Object

com.iplanet.dpro.session.service.cluster.MultiServerClusterMonitor

All Implemented Interfaces:

ClusterMonitor

public class MultiServerClusterMonitor
extends Object
implements 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

Constructor Summary

Constructors

Constructor and Description
MultiServerClusterMonitor(Debug sessionDebug, SessionServiceConfig serviceConfig, SessionServerConfig serverConfig)

Method Summary

Modifier and Type	Method and Description
boolean	checkServerUp(String serverID) Indicates if the specified server is up.
String	getCurrentHostServer(SessionID sid) 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 this ClusterMonitor should be shutdown.

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiServerClusterMonitor

public MultiServerClusterMonitor(Debug sessionDebug,
                                 SessionServiceConfig serviceConfig,
                                 SessionServerConfig serverConfig)
                          throws Exception

Parameters:

sessionDebug - The session debug instance.

serviceConfig - The configuration for the session service.

serverConfig - The configuration for the session server.

Throws:

Exception

Method Detail

isSiteUp

public boolean isSiteUp(String siteId)

Indicates if the specified site is up.

Specified by:

isSiteUp in interface ClusterMonitor

Parameters:

siteId - A possibly null Site Id.

Returns:

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

checkServerUp

public boolean checkServerUp(String serverID)

Indicates if the specified server is up.

Specified by:

checkServerUp in interface ClusterMonitor

Parameters:

serverID - server id

Returns:

true if server is up, false otherwise

getCurrentHostServer

public String getCurrentHostServer(SessionID sid)
                            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".

Specified by:

getCurrentHostServer in interface ClusterMonitor

Parameters:

sid - 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

public void shutdown()

Signals that this ClusterMonitor should be shutdown. Will signal the underlying ClusterStateService to cancel its runnable thread. Thread Safety: Synchronized to prevent possible multiple calls which would break state in the underlying GeneralRunnableTask framework.

Specified by:

shutdown in interface ClusterMonitor