com.hazelcast.map.mapstore.writebehind

Class WriteBehindStore

java.lang.Object

com.hazelcast.map.mapstore.AbstractMapDataStore<Data,Object>

com.hazelcast.map.mapstore.writebehind.WriteBehindStore

All Implemented Interfaces:

MapDataStore<Data,Object>

public class WriteBehindStore
extends AbstractMapDataStore<Data,Object>

TODO Holds current write behind state and should be included in migrations. Write behind map data store implementation. Created per every record-store.

Constructor Summary

Constructors

Constructor and Description
WriteBehindStore(MapStoreWrapper store, SerializationService serializationService, long writeDelayTime, int partitionId, boolean writeCoalescing)

Method Summary

Methods

Modifier and Type	Method and Description
Object	add(Data key, Object value, long now)
Object	addBackup(Data key, Object value, long time)
void	addTransient(Data key, long now)
void	cleanupStagingArea(long now)
Collection	flush()
Object	flush(Data key, Object value, long now, boolean backup) GOTCHA: When writeCoalescing is true, you may see more than one write operations to map store, e.g.
WriteBehindQueue<DelayedEntry>	getWriteBehindQueue()
Object	load(Data key)
boolean	loadable(Data key, long lastUpdateTime, long now) * Used in IMap.loadAll(boolean) calls.
Map	loadAll(Collection keys)
int	notFinishedOperationsCount()
void	remove(Data key, long now)
void	removeBackup(Data key, long time)
void	reset()
void	setWriteBehindProcessor(WriteBehindProcessor writeBehindProcessor)
void	setWriteBehindQueue(WriteBehindQueue<DelayedEntry> writeBehindQueue)

Methods inherited from class com.hazelcast.map.mapstore.AbstractMapDataStore

convertToObjectKeys, getStore, isPostProcessingMapStore, removeAll, toData, toObject

Methods inherited from class java.lang.Object

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

Constructor Detail

WriteBehindStore

public WriteBehindStore(MapStoreWrapper store,
                SerializationService serializationService,
                long writeDelayTime,
                int partitionId,
                boolean writeCoalescing)

Method Detail

setWriteBehindQueue

public void setWriteBehindQueue(WriteBehindQueue<DelayedEntry> writeBehindQueue)

add

public Object add(Data key,
         Object value,
         long now)

addTransient

public void addTransient(Data key,
                long now)

addBackup

public Object addBackup(Data key,
               Object value,
               long time)

remove

public void remove(Data key,
          long now)

removeBackup

public void removeBackup(Data key,
                long time)

reset

public void reset()

load

public Object load(Data key)

loadAll

public Map loadAll(Collection keys)

Specified by:

loadAll in interface MapDataStore<Data,Object>

Overrides:

loadAll in class AbstractMapDataStore<Data,Object>

loadable

public boolean loadable(Data key,
               long lastUpdateTime,
               long now)

* Used in IMap.loadAll(boolean) calls. If write-behind map-store feature enabled, some things may lead possible data inconsistencies. These are: - calling evict/evictAll. - calling remove. - not yet stored write behind queue operation.

With this method we can be sure that a key can be loadable from map-store or not.

Parameters:

key - to query whether loadable or not.

lastUpdateTime - last update time.

now - in mills

Returns:

true if loadable, otherwise false.

notFinishedOperationsCount

public int notFinishedOperationsCount()

flush

public Object flush(Data key,
           Object value,
           long now,
           boolean backup)

GOTCHA: When writeCoalescing is true, you may see more than one write operations to map store, e.g. if a flush during eviction and StoreWorker fetch the operation on same key, order of operations may be reflected differently to map store.

Parameters:

key - key to be flushed

value - value to be flushed

now - now in millis

backup - true calling this method for backup partition, false for owner partition.

Returns:

flushed value.

flush

public Collection flush()

cleanupStagingArea

public void cleanupStagingArea(long now)

getWriteBehindQueue

public WriteBehindQueue<DelayedEntry> getWriteBehindQueue()

setWriteBehindProcessor

public void setWriteBehindProcessor(WriteBehindProcessor writeBehindProcessor)