org.apache.zookeeper.server

Interface SessionTracker

All Known Implementing Classes:

LeaderSessionTracker, LearnerSessionTracker, LocalSessionTracker, SessionTrackerImpl, UpgradeableSessionTracker

public interface SessionTracker

This is the basic interface that ZooKeeperServer uses to track sessions. The standalone and leader ZooKeeperServer use the same SessionTracker. The FollowerZooKeeperServer uses a SessionTracker which is basically a simple shell to track information to be forwarded to the leader.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	SessionTracker.Session
static interface	SessionTracker.SessionExpirer

Method Summary

Modifier and Type	Method and Description
boolean	addGlobalSession(long id, int to) Add a global session to those being tracked.
boolean	addSession(long id, int to) Add a session to those being tracked.
void	checkGlobalSession(long sessionId, Object owner) Strictly check that a given session is a global session or not
void	checkSession(long sessionId, Object owner) Checks whether the SessionTracker is aware of this session, the session is still active, and the owner matches.
long	createSession(int sessionTimeout)
void	dumpSessions(PrintWriter pwriter) Text dump of session information, suitable for debugging.
Map<Long,Set<Long>>	getSessionExpiryMap() Returns a mapping of time to session IDs that expire at that time.
boolean	isTrackingSession(long sessionId)
void	removeSession(long sessionId)
void	setOwner(long id, Object owner)
void	setSessionClosing(long sessionId) Mark that the session is in the process of closing.
void	shutdown()
boolean	touchSession(long sessionId, int sessionTimeout)

Method Detail

createSession

long createSession(int sessionTimeout)

addGlobalSession

boolean addGlobalSession(long id,
                         int to)

Add a global session to those being tracked.

Parameters:

id - sessionId

to - sessionTimeout

Returns:

whether the session was newly added (if false, already existed)

addSession

boolean addSession(long id,
                   int to)

Add a session to those being tracked. The session is added as a local session if they are enabled, otherwise as global.

Parameters:

id - sessionId

to - sessionTimeout

Returns:

whether the session was newly added (if false, already existed)

touchSession

boolean touchSession(long sessionId,
                     int sessionTimeout)

Parameters:

sessionId -

sessionTimeout -

Returns:

false if session is no longer active

setSessionClosing

void setSessionClosing(long sessionId)

Mark that the session is in the process of closing.

Parameters:

sessionId -

shutdown

void shutdown()

removeSession

void removeSession(long sessionId)

Parameters:

sessionId -

isTrackingSession

boolean isTrackingSession(long sessionId)

Parameters:

sessionId -

Returns:

whether or not the SessionTracker is aware of this session

checkSession

void checkSession(long sessionId,
                  Object owner)
           throws KeeperException.SessionExpiredException,
                  KeeperException.SessionMovedException,
                  KeeperException.UnknownSessionException

Checks whether the SessionTracker is aware of this session, the session is still active, and the owner matches. If the owner wasn't previously set, this sets the owner of the session. UnknownSessionException should never been thrown to the client. It is only used internally to deal with possible local session from other machine

Parameters:

sessionId -

owner -

Throws:

KeeperException.SessionExpiredException

KeeperException.SessionMovedException

KeeperException.UnknownSessionException

checkGlobalSession

void checkGlobalSession(long sessionId,
                        Object owner)
                 throws KeeperException.SessionExpiredException,
                        KeeperException.SessionMovedException

Strictly check that a given session is a global session or not

Parameters:

sessionId -

owner -

Throws:

KeeperException.SessionExpiredException

KeeperException.SessionMovedException

setOwner

void setOwner(long id,
              Object owner)
       throws KeeperException.SessionExpiredException

Throws:

KeeperException.SessionExpiredException

dumpSessions

void dumpSessions(PrintWriter pwriter)

Text dump of session information, suitable for debugging.

Parameters:

pwriter - the output writer

getSessionExpiryMap

Map<Long,Set<Long>> getSessionExpiryMap()

Returns a mapping of time to session IDs that expire at that time.