# Package org.apache.ignite.internal.processors.cache.distributed.dht.preloader

Interface Summary
IgniteHistoricalIterator: Iterator that provides history of updates for a subset of partitions.
PartitionsExchangeAware: Interface which allows to subscribe a component for partition map exchange events (via `GridCachePartitionExchangeManager.registerExchangeAwareComponent(PartitionsExchangeAware)`).

Class Summary
CacheGroupAffinityMessage: Information about affinity assignment.
CachePartitionFullCountersMap
CachePartitionPartialCountersMap
FinishPreloadingTask: A task for finishing preloading future in exchange worker thread.
ForceRebalanceExchangeTask
GridDhtForceKeysFuture<K,​V>: Force keys request future.
GridDhtForceKeysRequest: Force keys request.
GridDhtForceKeysResponse: Force keys response.
GridDhtPartitionDemander: Thread pool for requesting partitions from other nodes and populating local cache.
GridDhtPartitionDemander.RebalanceFuture: The future is created for each topology version if some partitions should present by affinity and completed when all partitions are transferred.
GridDhtPartitionDemandLegacyMessage: Partition demand request.
GridDhtPartitionDemandMessage: Partition demand request.
GridDhtPartitionExchangeId: Exchange ID.
GridDhtPartitionFullMap: Full partition map from all nodes.
GridDhtPartitionMap: Partition map from single node.
GridDhtPartitionsAbstractMessage: Request for single partition info.
GridDhtPartitionsExchangeFuture: Future for exchanging partition maps.
GridDhtPartitionsFullMessage: Information about partitions of all nodes in topology.
GridDhtPartitionsSingleMessage: Information about partitions of a single node.
GridDhtPartitionsSingleRequest: Request for single partition info.
GridDhtPartitionSupplier: Class for supplying partitions to demanding nodes.
GridDhtPartitionSupplyMessage: Partition supply message.
GridDhtPartitionSupplyMessageV2: Supply message with supplier error transfer support.
GridDhtPreloader: DHT cache preloader.
GridDhtPreloaderAssignments: Partition to node assignments.
IgniteDhtDemandedPartitionsMap: Map of partitions demanded during rebalancing.
IgniteDhtPartitionCountersMap: Partition counters map.
IgniteDhtPartitionCountersMap2: Partition counters map.
IgniteDhtPartitionHistorySuppliersMap
IgniteDhtPartitionsToReloadMap: Partition reload map.
IgniteRebalanceIteratorImpl: Default iterator for rebalancing.
InitNewCoordinatorFuture
RebalanceReassignExchangeTask
StopCachesOnClientReconnectExchangeTask
SupplyPartitionInfo: Information about supplier for specific partition.

Enum Summary
GridDhtPartitionsExchangeFuture.ExchangeType

Exception Summary
IgniteHistoricalIteratorException: Thrown when `IgniteHistoricalIterator` cannot iterate over WAL for some reason.