org.apache.zookeeper.server.watch

Class WatchManager

java.lang.Object

org.apache.zookeeper.server.watch.WatchManager

All Implemented Interfaces:

IWatchManager

public class WatchManager
extends Object
implements IWatchManager

This class manages watches. It allows watches to be associated with a string and removes watchers and their watches in addition to managing triggers.

Constructor Summary

Constructors

Constructor and Description
WatchManager()

Method Summary

Modifier and Type	Method and Description
boolean	addWatch(String path, Watcher watcher) Add watch to specific path.
boolean	addWatch(String path, Watcher watcher, WatcherMode watcherMode) Add watch to specific path.
boolean	containsWatcher(String path, Watcher watcher) Checks the specified watcher exists for the given path.
boolean	containsWatcher(String path, Watcher watcher, WatcherMode watcherMode) Checks the specified watcher exists for the given path and mode.
void	dumpWatches(PrintWriter pwriter, boolean byPath) String representation of watches.
WatchesReport	getWatches() Returns a watch report.
WatchesPathReport	getWatchesByPath() Returns a watch report by path.
WatchesSummary	getWatchesSummary() Returns a watch summary.
boolean	removeWatcher(String path, Watcher watcher) Removes the specified watcher for the given path.
boolean	removeWatcher(String path, Watcher watcher, WatcherMode watcherMode) Removes the specified watcher for the given path and mode.
void	removeWatcher(Watcher watcher) The entry to remove the watcher when the cnxn is closed.
void	shutdown() Clean up the watch manager.
int	size() Get the size of watchers.
String	toString()
WatcherOrBitSet	triggerWatch(String path, Watcher.Event.EventType type, long zxid, List<ACL> acl) Distribute the watch event for the given path.
WatcherOrBitSet	triggerWatch(String path, Watcher.Event.EventType type, long zxid, List<ACL> acl, WatcherOrBitSet supress) Distribute the watch event for the given path, but ignore those suppressed ones.

Methods inherited from class java.lang.Object

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

Constructor Detail

WatchManager

public WatchManager()

Method Detail

size

public int size()

Description copied from interface: IWatchManager

Get the size of watchers.

Specified by:

size in interface IWatchManager

Returns:

the watchers number managed in this class.

addWatch

public boolean addWatch(String path,
                        Watcher watcher)

Description copied from interface: IWatchManager

Add watch to specific path.

Specified by:

addWatch in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

Returns:

true if the watcher added is not already present

addWatch

public boolean addWatch(String path,
                        Watcher watcher,
                        WatcherMode watcherMode)

Description copied from interface: IWatchManager

Add watch to specific path.

Specified by:

addWatch in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

watcherMode - the watcher mode to use

Returns:

true if the watcher added is not already present

removeWatcher

public void removeWatcher(Watcher watcher)

Description copied from interface: IWatchManager

The entry to remove the watcher when the cnxn is closed.

Specified by:

removeWatcher in interface IWatchManager

Parameters:

watcher - watcher object reference

triggerWatch

public WatcherOrBitSet triggerWatch(String path,
                                    Watcher.Event.EventType type,
                                    long zxid,
                                    List<ACL> acl)

Description copied from interface: IWatchManager

Distribute the watch event for the given path.

Specified by:

triggerWatch in interface IWatchManager

Parameters:

path - znode path

type - the watch event type

zxid - the zxid for the corresponding change that triggered this event

acl - ACL of the znode in path

Returns:

the watchers have been notified

triggerWatch

public WatcherOrBitSet triggerWatch(String path,
                                    Watcher.Event.EventType type,
                                    long zxid,
                                    List<ACL> acl,
                                    WatcherOrBitSet supress)

Description copied from interface: IWatchManager

Distribute the watch event for the given path, but ignore those suppressed ones.

Specified by:

triggerWatch in interface IWatchManager

Parameters:

path - znode path

type - the watch event type

zxid - the zxid for the corresponding change that triggered this event

supress - the suppressed watcher set

Returns:

the watchers have been notified

toString

public String toString()

Overrides:

toString in class Object

dumpWatches

public void dumpWatches(PrintWriter pwriter,
                        boolean byPath)

Description copied from interface: IWatchManager

String representation of watches. Warning, may be large!

Specified by:

dumpWatches in interface IWatchManager

Parameters:

pwriter - the writer to dump the watches

byPath - iff true output watches by paths, otw output watches by connection

containsWatcher

public boolean containsWatcher(String path,
                               Watcher watcher)

Description copied from interface: IWatchManager

Checks the specified watcher exists for the given path.

Specified by:

containsWatcher in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

Returns:

true if the watcher exists, false otherwise

containsWatcher

public boolean containsWatcher(String path,
                               Watcher watcher,
                               WatcherMode watcherMode)

Description copied from interface: IWatchManager

Checks the specified watcher exists for the given path and mode.

Specified by:

containsWatcher in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

watcherMode - watcher mode, null for any mode

Returns:

true if the watcher exists, false otherwise

removeWatcher

public boolean removeWatcher(String path,
                             Watcher watcher,
                             WatcherMode watcherMode)

Description copied from interface: IWatchManager

Removes the specified watcher for the given path and mode.

Specified by:

removeWatcher in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

watcherMode - watcher mode, null to remove all modes

Returns:

true if the watcher successfully removed, false otherwise

removeWatcher

public boolean removeWatcher(String path,
                             Watcher watcher)

Description copied from interface: IWatchManager

Removes the specified watcher for the given path.

Specified by:

removeWatcher in interface IWatchManager

Parameters:

path - znode path

watcher - watcher object reference

Returns:

true if the watcher successfully removed, false otherwise

getWatches

public WatchesReport getWatches()

Description copied from interface: IWatchManager

Returns a watch report.

Specified by:

getWatches in interface IWatchManager

Returns:

watch report

See Also:

WatchesReport

getWatchesByPath

public WatchesPathReport getWatchesByPath()

Description copied from interface: IWatchManager

Returns a watch report by path.

Specified by:

getWatchesByPath in interface IWatchManager

Returns:

watch report

See Also:

WatchesPathReport

getWatchesSummary

public WatchesSummary getWatchesSummary()

Description copied from interface: IWatchManager

Returns a watch summary.

Specified by:

getWatchesSummary in interface IWatchManager

Returns:

watch summary

See Also:

WatchesSummary

shutdown

public void shutdown()

Description copied from interface: IWatchManager

Clean up the watch manager.

Specified by:

shutdown in interface IWatchManager