Package com.tangosol.coherence.federation

Interface ChangeRecord<K,V>

public interface ChangeRecord<K,V>

Provides a mechanism to represent and mutate a Cache Entry that was changed in a Federated Cache.

ChangeRecords are typically provided to EventInterceptors as part of a FederatedChangeEvent for the purpose of inspecting and possibly modifying an entry prior to it being committed.

EventInterceptors may choose to reject the change or change the value. When no change is specified the modified value is committed.

Any updates to a ChangeRecord will overwrite the modified Entry and thus the updated value when the change is committed.

When ChangeRecord is for a local participant, the original and local entry will be the same.

Author:

bb

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	ChangeRecord.Entry<K,V>	Represents the key, value and name of the Participant from which the entry originated.

Method Summary

Modifier and Type	Method	Description
ChangeRecord<Binary,Binary>	getBinaryChangeRecord()	Obtain a Binary representation of the ChangeRecord, with the key and values in Binary format.
com.tangosol.net.events.federation.FederatedChangeEvent.Type	getEventType()	The type of the FederatedChangeEvent.
K	getKey()	Obtain the key of the changed ChangeRecord.Entry.
ChangeRecord.Entry<K,V>	getLocalEntry()	Obtains a representation of ChangeRecord.Entry as it appears in the local participant.
ChangeRecord.Entry<K,V>	getModifiedEntry()	Obtain a representation of the modified ChangeRecord.Entry.
ChangeRecord.Entry<K,V>	getOriginalEntry()	Obtain a representation of the ChangeRecord.Entry prior to any changes occurring.
boolean	isDeleted()	Determine if the modified entry in the ChangeRecord was deleted.
boolean	isLocalOnly()	Determine whether the change represented by this ChangeRecord is local only, therefore not federated.
boolean	isSynthetic()	Determine if this Entry has been synthetically mutated.
void	rejectChange()	Signal that the modified ChangeRecord.Entry should not be applied.
void	setLocalOnly(boolean bLocal)	Set the local only flag to indicate that the change is not federated.
void	setValue(V newValue)	Update the modified ChangeRecord.Entry value.
void	setValue(V newValue, boolean fSynthetic)	Update the modified ChangeRecord.Entry value with a synthetic flag.
<T> void	update(ValueUpdater<V,T> updater, T oValue)	Update the modified Entry's value using the given ValueUpdater.

Method Detail

getKey

K getKey()

Obtain the key of the changed ChangeRecord.Entry.

Returns:

the entry key

getModifiedEntry

ChangeRecord.Entry<K,V> getModifiedEntry()

Obtain a representation of the modified ChangeRecord.Entry.

This ChangeRecord.Entry will be used to modify the associated ChangeRecord.Entry in the destination participant.

Returns:

modified entry

getOriginalEntry

ChangeRecord.Entry<K,V> getOriginalEntry()

Obtain a representation of the ChangeRecord.Entry prior to any changes occurring.

This is typically a representation of the ChangeRecord.Entry at the source participant prior to a change occurring.

Returns:

the original entry

getLocalEntry

ChangeRecord.Entry<K,V> getLocalEntry()

Obtains a representation of ChangeRecord.Entry as it appears in the local participant.

Returns:

the local entry

getEventType

com.tangosol.net.events.federation.FederatedChangeEvent.Type getEventType()

The type of the FederatedChangeEvent.

Returns:

the type of the FederatedChangeEvent

Since:

12.2.1.0.2

setValue

void setValue(V newValue)

Update the modified ChangeRecord.Entry value.

This method can potentially cause the change to be propagated back to the origin participant. Care must be taken to avoid any recursive ping-pong cycles.

Parameters:

newValue - new value for the modified entry

setValue

void setValue(V newValue,
              boolean fSynthetic)

Update the modified ChangeRecord.Entry value with a synthetic flag.

This method can potentially cause the change to be propagated back to the origin participant. Care must be taken to avoid any recursive ping-pong cycles.

Note: Marking a change as synthetic will have different behavior depending on the federation event type: COMMITTING_LOCAL - the change will not be federated to other clusters and CacheStores will not be called. REPLICATING - setting the change synthetic is not allowed. An UnsupportedOperationException will be thrown. COMMITTING_REMOTE - the change will be applied as a synthetic change. CacheStores will not be triggered and federation will not forward the change to other clusters from this destination cluster.

Parameters:

newValue - new value for the modified entry

fSynthetic - a flag to indicate whether the update is synthetic

Since:

12.2.1.4.1

update

<T> void update(ValueUpdater<V,T> updater,
                T oValue)

Update the modified Entry's value using the given ValueUpdater.

Parameters:

updater - a ValueUpdater used to modify the Entry's value

oValue - the new value for this Entry

rejectChange

void rejectChange()

Signal that the modified ChangeRecord.Entry should not be applied. The local ChangeRecord.Entry should remain unchanged.

isDeleted

boolean isDeleted()

Determine if the modified entry in the ChangeRecord was deleted.

Returns:

true if the entry was deleted

getBinaryChangeRecord

ChangeRecord<Binary,Binary> getBinaryChangeRecord()

Obtain a Binary representation of the ChangeRecord, with the key and values in Binary format.

Returns:

Binary ChangeRecord

setLocalOnly

void setLocalOnly(boolean bLocal)

Set the local only flag to indicate that the change is not federated.

Note: this setting is only applicable to FederatedChangeEvent.Type.COMMITTING_LOCAL events.

Parameters:

bLocal - a flag to indicate whether to keep the change local only

Since:

12.2.1.0.3

isLocalOnly

boolean isLocalOnly()

Determine whether the change represented by this ChangeRecord is local only, therefore not federated.

Note: this setting is only applicable to FederatedChangeEvent.Type.COMMITTING_LOCAL events.

Returns:

a boolean value to indicate whether the change is local only

Since:

12.2.1.0.3

isSynthetic

boolean isSynthetic()

Determine if this Entry has been synthetically mutated. This method returns false if either a non-synthetic update was made or the entry has not been modified.

Returns:

true if the Entry has been synthetically mutated

Since:

12.2.1.4.1