org.infinispan.conflict

Interface ConflictManager<K,V>

public interface ConflictManager<K,V>

Since:

9.1

Author:

Ryan Emerson

Method Summary

Modifier and Type	Method and Description
Map<Address,InternalCacheValue<V>>	getAllVersions(K key) Get all CacheEntry's that exists for a given key.
Stream<Map<Address,CacheEntry<K,V>>>	getConflicts() Returns a stream of conflicts detected in the cluster.
boolean	isConflictResolutionInProgress()
boolean	isStateTransferInProgress()
void	resolveConflicts() Utilises getConflicts() to discover conflicts between Key replicas and utilises the configured EntryMergePolicy to determine which entry should take precedence.
void	resolveConflicts(EntryMergePolicy<K,V> mergePolicy) Utilises getConflicts() to discover conflicts between Key replicas and utilises the provided EntryMergePolicy to determine which entry should take precedence.

Method Detail

getAllVersions

Map<Address,InternalCacheValue<V>> getAllVersions(K key)

Get all CacheEntry's that exists for a given key. Note, concurrent calls to this method for the same key will utilise the same CompletableFuture inside this method and consequently return the same results as all other invocations. If this method is invoked during state transfer it will block until rehashing has completed. Similarly, if state transfer is initiated during an invocation of this method and rehashing affects the segments of the provided key, the initial requests for the entries versions are cancelled and re-attempted once state transfer has completed. This method utilises the addresses of the local DistributionInfo.writeOwners() to request values for a given key. If a value does not exist for a key at one of the addresses, then a null valued is mapped to said address.

Parameters:

key - the key for which associated entries are to be returned

Returns:

a map of an address and it's associated CacheEntry

Throws:

CacheException - if one or more versions of a key cannot be retrieved.

getConflicts

Stream<Map<Address,CacheEntry<K,V>>> getConflicts()

Returns a stream of conflicts detected in the cluster. This is a lazily-loaded stream which searches for conflicts by sequentially fetching cache segments from their respective owner nodes. If a rebalance is initiated whilst the stream is fetching a cache segment, then a CacheException is thrown when executing the stream.

Returns:

a stream of Map> for all conflicts detected throughout this cache.

Throws:

IllegalStateException - if called whilst a previous conflicts stream is still executing or state transfer is in progress.

resolveConflicts

void resolveConflicts()

Utilises getConflicts() to discover conflicts between Key replicas and utilises the configured EntryMergePolicy to determine which entry should take precedence. The resulting CacheEntry is then applied on all replicas in the cluster.

resolveConflicts

void resolveConflicts(EntryMergePolicy<K,V> mergePolicy)

Utilises getConflicts() to discover conflicts between Key replicas and utilises the provided EntryMergePolicy to determine which entry should take precedence. The resulting CacheEntry is then applied on all replicas in the cluster.

Parameters:

mergePolicy - the policy to be applied to all detected conflicts

isStateTransferInProgress

boolean isStateTransferInProgress()

Returns:

true if a state transfer is currently in progress.

isConflictResolutionInProgress

boolean isConflictResolutionInProgress()

Returns:

true if conflict resolution is in progress. This can happen if the user has multiple threads interacting with the ConflictManager or if a Split-brain merge is in progress.