org.gridgain.grid.kernal.processors.dr

Class GridDrReceiverConflictContextImpl<K,V>

java.lang.Object

org.gridgain.grid.kernal.processors.dr.GridDrReceiverConflictContextImpl<K,V>

All Implemented Interfaces:

GridDrReceiverCacheConflictContext<K,V>

public class GridDrReceiverConflictContextImpl<K,V>
extends Object
implements GridDrReceiverCacheConflictContext<K,V>

Data center replication conflict context implementation.

Constructor Summary

Constructors

Constructor and Description
GridDrReceiverConflictContextImpl(GridDrEntry<K,V> oldEntry, GridDrEntry<K,V> newEntry) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
long	expireTime()
boolean	explicitTtl()
boolean	isMerge()
boolean	isUseNew()
boolean	isUseOld()
void	merge(V mergeVal, long ttl) Force data center replication engine to use neither old, nor new, but some other value passed as argument.
V	mergeValue()
GridDrEntry<K,V>	newEntry() Gets new cache entry.
GridDrEntry<K,V>	oldEntry() Gets old (existing) cache entry.
String	toString()
long	ttl()
void	useNew() Force data center replication receiver cache to apply new entry thus overwriting old (existing) entry.
void	useOld() Force data center replication receiver cache to ignore new entry and leave old (existing) entry unchanged.

Methods inherited from class java.lang.Object

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

Constructor Detail

GridDrReceiverConflictContextImpl

public GridDrReceiverConflictContextImpl(GridDrEntry<K,V> oldEntry,
                                 GridDrEntry<K,V> newEntry)

Constructor.

Parameters:

oldEntry - Old entry.

newEntry - New entry.

Method Detail

oldEntry

public GridDrEntry<K,V> oldEntry()

Gets old (existing) cache entry.

Specified by:

oldEntry in interface GridDrReceiverCacheConflictContext<K,V>

Returns:

Old (existing) cache entry.

newEntry

public GridDrEntry<K,V> newEntry()

Gets new cache entry.

Specified by:

newEntry in interface GridDrReceiverCacheConflictContext<K,V>

Returns:

New cache entry.

useOld

public void useOld()

Force data center replication receiver cache to ignore new entry and leave old (existing) entry unchanged.

Specified by:

useOld in interface GridDrReceiverCacheConflictContext<K,V>

useNew

public void useNew()

Force data center replication receiver cache to apply new entry thus overwriting old (existing) entry.

Note that updates from remote data centers always have explicit TTL , while local data center updates will only have explicit TTL in case GridCacheEntry.timeToLive(long) was called before update. In the latter case new entry will pick TTL of the old (existing) entry, even if it was set through update from remote data center. it means that depending on concurrent update timings new update might pick unexpected TTL. For example, consider that three updates of the same key are performed: local update with explicit TTL (1) followed by another local update without explicit TTL (2) and one remote update (3). In this case you might expect that update (2) will pick TTL set during update (1). However, in case update (3) occurrs between (1) and (2) and it overwrites (1) during conflict resolution, then update (2) will pick TTL of update (3). To have predictable TTL in such cases you should either always set it explicitly through GridCacheEntry.timeToLive(long) or use GridDrReceiverCacheConflictContext.merge(Object, long).

Specified by:

useNew in interface GridDrReceiverCacheConflictContext<K,V>

merge

public void merge(@Nullable
         V mergeVal,
         long ttl)

Force data center replication engine to use neither old, nor new, but some other value passed as argument. In this case old value will be replaced with merge value and update will be considered as local (i.e. GridConfiguration.getDataCenterId() will be used).

Also in case of merge you have to specify new TTL explicitly. For unlimited TTL use 0.

Specified by:

merge in interface GridDrReceiverCacheConflictContext<K,V>

Parameters:

mergeVal - Merge value or null to force remove.

ttl - Time to live in milliseconds.

isUseOld

public boolean isUseOld()

Returns:

True in case old value should be used.

isUseNew

public boolean isUseNew()

Returns:

True in case new value should be used.

isMerge

public boolean isMerge()

Returns:

True in case merge is to be performed.

mergeValue

@Nullable
public V mergeValue()

Returns:

Value to merge (if any).

ttl

public long ttl()

Returns:

TTL.

expireTime

public long expireTime()

Returns:

Expire time.

explicitTtl

public boolean explicitTtl()

Returns:

Explicit TTL flag.

toString

public String toString()

Overrides:

toString in class Object