Package org.apache.accumulo.server.conf.util

Class PropSnapshot

java.lang.Object

org.apache.accumulo.server.conf.util.PropSnapshot

All Implemented Interfaces:

PropChangeListener

public class PropSnapshot
extends Object
implements PropChangeListener

This class provides a secondary, local cache of properties and is intended to be used to optimize constructing a configuration hierarchy from the underlying properties stored in ZooKeeper.

Configurations and especially the derivers use an updateCount to detect configuration changes. The updateCount is checked frequently and the configuration hierarchy rebuilt when a change is detected.

Method Summary

Modifier and Type	Method	Description
void	cacheChangeEvent(PropStoreKey<?> eventPropKey)	Signal that a cache change event occurred - cache change events occur on eviction or invalidation of the cache entry.
void	connectionEvent()	A ZooKeeper connection event (session closed, expired...) and that
static PropSnapshot	create(PropStoreKey<?> propStoreKey, PropStore propStore)
void	deleteEvent(PropStoreKey<?> eventPropKey)	Signal that the node had been deleted from ZooKeeper.
@NonNull VersionedProperties	getVersionedProperties()	Get the current snapshot - updating if necessary.
void	requireUpdate()	Signal the current snapshot is invalid and needs to be updated on next access.
void	zkChangeEvent(PropStoreKey<?> eventPropKey)	Signal that a ZooKeeper data change event occurred and that the data has changed.

Methods inherited from class java.lang.Object

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

Method Detail

create

public static PropSnapshot create(PropStoreKey<?> propStoreKey,
                                  PropStore propStore)

getVersionedProperties

public @NonNull VersionedProperties getVersionedProperties()

Get the current snapshot - updating if necessary.

Returns:

the current property snapshot.

requireUpdate

public void requireUpdate()

Signal the current snapshot is invalid and needs to be updated on next access.

zkChangeEvent

public void zkChangeEvent(PropStoreKey<?> eventPropKey)

Description copied from interface: PropChangeListener

Signal that a ZooKeeper data change event occurred and that the data has changed.

Specified by:

zkChangeEvent in interface PropChangeListener

cacheChangeEvent

public void cacheChangeEvent(PropStoreKey<?> eventPropKey)

Description copied from interface: PropChangeListener

Signal that a cache change event occurred - cache change events occur on eviction or invalidation of the cache entry. The underlying data may or may not have changed.

Specified by:

cacheChangeEvent in interface PropChangeListener

deleteEvent

public void deleteEvent(PropStoreKey<?> eventPropKey)

Description copied from interface: PropChangeListener

Signal that the node had been deleted from ZooKeeper.

Specified by:

deleteEvent in interface PropChangeListener

connectionEvent

public void connectionEvent()

Description copied from interface: PropChangeListener

A ZooKeeper connection event (session closed, expired...) and that

Specified by:

connectionEvent in interface PropChangeListener