GridCachePreloader (Ignite 2.11.1)

All Known Implementing Classes:

GridCachePreloaderAdapter, GridDhtPreloader
```
public interface GridCachePreloader
```
Cache preloader that is responsible for loading cache entries either from remote nodes (for distributed cache) or anywhere else at cache startup.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`GridDhtPartitionDemander.RebalanceFuture`	`addAssignments(GridDhtPreloaderAssignments assignments, boolean forcePreload, long rebalanceId, GridDhtPartitionDemander.RebalanceFuture next, @Nullable GridCompoundFuture<Boolean,Boolean> forcedRebFut, GridCompoundFuture<Boolean,Boolean> compatibleRebFut)` Adds assignments to preloader.
`long`	`batchesPrefetchCount()` The number of batches generated by supply node at rebalancing procedure start.
`int`	`batchSize()` The supply message size in bytes to be loaded within a single rebalance batch.
`void`	`dumpDebugInfo()` Dumps debug information.
`void`	`finishPreloading(AffinityTopologyVersion topVer, long rebalanceId)` Finish preloading for given topology version.
`IgniteInternalFuture<Boolean>`	`forceRebalance()` Force Rebalance process.
`@Nullable GridDhtPreloaderAssignments`	`generateAssignments(GridDhtPartitionExchangeId exchId, @Nullable GridDhtPartitionsExchangeFuture exchFut)`
`void`	`handleDemandMessage(int idx, UUID id, GridDhtPartitionDemandMessage d)` Handles Demand message.
`void`	`handleSupplyMessage(UUID id, GridDhtPartitionSupplyMessage s)` Handles Supply message.
`boolean`	`needForceKeys()`
`void`	`onInitialExchangeComplete(@Nullable Throwable err)` Callback by exchange manager when initial partition exchange is complete.
`void`	`onKernalStop()` Kernal stop callback.
`void`	`onReconnected()` Client reconnected callback.
`void`	`onTopologyChanged(GridDhtPartitionsExchangeFuture lastFut)`
`void`	`pause()` Pause preloader.
`IgniteInternalFuture<Boolean>`	`rebalanceFuture()`
`boolean`	`rebalanceRequired(GridDhtPartitionsExchangeFuture exchFut)`
`GridDhtFuture<Object>`	`request(GridCacheContext cctx, Collection<KeyCacheObject> keys, AffinityTopologyVersion topVer)` Requests that preloader sends the request for the key.
`GridDhtFuture<Object>`	`request(GridCacheContext cctx, GridNearAtomicAbstractUpdateRequest req, AffinityTopologyVersion topVer)` Requests that preloader sends the request for the key.
`void`	`resume()` Resume preloader.
`void`	`start()` Starts preloading.
`IgniteInternalFuture<Object>`	`startFuture()`
`IgniteInternalFuture<?>`	`syncFuture()`
`long`	`throttle()` Time in milliseconds to wait between rebalance messages to avoid overloading of CPU or network.
`long`	`timeout()` Rebalance timeout for supply and demand messages in milliseconds.

- Method Detail
  - start
```
void start()
    throws IgniteCheckedException
```
    Starts preloading.
    
    Throws:
    
    IgniteCheckedException - If start failed.
  - onKernalStop
```
void onKernalStop()
```
    Kernal stop callback.
  - onReconnected
```
void onReconnected()
```
    Client reconnected callback.
  - onInitialExchangeComplete
```
void onInitialExchangeComplete(@Nullable
                               @Nullable Throwable err)
```
    Callback by exchange manager when initial partition exchange is complete.
    
    Parameters:
    
    err - Error, if any happened on initial exchange.
  - rebalanceRequired
```
boolean rebalanceRequired(GridDhtPartitionsExchangeFuture exchFut)
```
    Parameters:
    
    exchFut - Completed exchange future.
    
    Returns:
    
    True if rebalance should be started (previous will be interrupted).
  - generateAssignments
```
@Nullable
@Nullable GridDhtPreloaderAssignments generateAssignments(GridDhtPartitionExchangeId exchId,
                                                                    @Nullable
                                                                    @Nullable GridDhtPartitionsExchangeFuture exchFut)
```
    Parameters:
    
    exchId - Exchange ID.
    
    exchFut - Completed exchange future. Can be null if forced or reassigned generation occurs.
    
    Returns:
    
    Partition assignments which will be requested from supplier nodes.
  - addAssignments
```
GridDhtPartitionDemander.RebalanceFuture addAssignments(GridDhtPreloaderAssignments assignments,
                                                        boolean forcePreload,
                                                        long rebalanceId,
                                                        GridDhtPartitionDemander.RebalanceFuture next,
                                                        @Nullable
                                                        @Nullable GridCompoundFuture<Boolean,Boolean> forcedRebFut,
                                                        GridCompoundFuture<Boolean,Boolean> compatibleRebFut)
```
    Adds assignments to preloader.
    
    Parameters:
    
    assignments - Assignments to add.
    
    forcePreload - True if preload requested by ForceRebalanceExchangeTask.
    
    rebalanceId - Rebalance id created by exchange thread.
    
    next - Rebalance's future follows after the current one.
    
    forcedRebFut - External future for forced rebalance.
    
    compatibleRebFut - Future for waiting for compatible rebalances.
    
    Returns:
    
    Future if rebalance was planned or null.
  - startFuture
```
IgniteInternalFuture<Object> startFuture()
```
    Returns:
    
    Future which will complete when preloader is safe to use.
  - syncFuture
```
IgniteInternalFuture<?> syncFuture()
```
    Returns:
    
    Future which will complete when initial preloading is finished.
  - rebalanceFuture
```
IgniteInternalFuture<Boolean> rebalanceFuture()
```
    Returns:
    
    Future which will complete when preloading finishes on current topology. Future result is true in case rebalancing successfully finished at current topology. Future result is false in case rebalancing cancelled or finished with missed partitions and will be restarted at current or pending topology.
  - needForceKeys
```
boolean needForceKeys()
```
    Returns:
    
    true if there is no need to force keys preloading (e.g. rebalancing has been completed).
  - request
```
GridDhtFuture<Object> request(GridCacheContext cctx,
                              Collection<KeyCacheObject> keys,
                              AffinityTopologyVersion topVer)
```
    Requests that preloader sends the request for the key.
    
    Parameters:
    
    cctx - Cache context.
    
    keys - Keys to request.
    
    topVer - Topology version, -1 if not required.
    
    Returns:
    
    Future to complete when all keys are preloaded.
  - request
```
GridDhtFuture<Object> request(GridCacheContext cctx,
                              GridNearAtomicAbstractUpdateRequest req,
                              AffinityTopologyVersion topVer)
```
    Requests that preloader sends the request for the key.
    
    Parameters:
    
    cctx - Cache context.
    
    req - Message with keys to request.
    
    topVer - Topology version, -1 if not required.
    
    Returns:
    
    Future to complete when all keys are preloaded.
  - forceRebalance
```
IgniteInternalFuture<Boolean> forceRebalance()
```
    Force Rebalance process.
  - handleSupplyMessage
```
void handleSupplyMessage(UUID id,
                         GridDhtPartitionSupplyMessage s)
```
    Handles Supply message.
    
    Parameters:
    
    id - Node Id.
    
    s - Supply message.
  - handleDemandMessage
```
void handleDemandMessage(int idx,
                         UUID id,
                         GridDhtPartitionDemandMessage d)
```
    Handles Demand message.
    
    Parameters:
    
    idx - Index.
    
    id - Node Id.
    
    d - Demand message.
  - onTopologyChanged
```
void onTopologyChanged(GridDhtPartitionsExchangeFuture lastFut)
```
    Parameters:
    
    lastFut - Last future.
  - dumpDebugInfo
```
void dumpDebugInfo()
```
    Dumps debug information.
  - pause
```
void pause()
```
    Pause preloader.
  - resume
```
void resume()
```
    Resume preloader.
  - timeout
```
long timeout()
```
    Rebalance timeout for supply and demand messages in milliseconds.
    The IgniteConfiguration.getRebalanceTimeout() will be used by default. If an Ignite's configuration value is not provided than the CacheConfiguration.getRebalanceTimeout() will be used instead.
    
    Returns:
    
    Rebalance message timeout in milliseconds.
  - batchesPrefetchCount
```
long batchesPrefetchCount()
```
    The number of batches generated by supply node at rebalancing procedure start.
    The IgniteConfiguration.getRebalanceBatchesPrefetchCount() will be used by default. If an Ignite's configuration value is not provided than the CacheConfiguration.getRebalanceBatchesPrefetchCount() will be used instead.
    
    Returns:
    
    The number of batches prefetch count.
  - throttle
```
long throttle()
```
    Time in milliseconds to wait between rebalance messages to avoid overloading of CPU or network.
    The IgniteConfiguration.getRebalanceThrottle() will be used by default. If an Ignite's configuration value is not provided than the CacheConfiguration.getRebalanceThrottle() will be used instead.
    
    Returns:
    
    Time in milliseconds to wait between rebalance messages, 0 to disable throttling.
  - batchSize
```
int batchSize()
```
    The supply message size in bytes to be loaded within a single rebalance batch.
    The IgniteConfiguration.getRebalanceBatchSize() will be used by default. If an Ignite's configuration value is not provided than the CacheConfiguration.getRebalanceBatchSize() will be used instead.
    
    Returns:
    
    Rebalance message size in bytes.
  - finishPreloading
```
void finishPreloading(AffinityTopologyVersion topVer,
                      long rebalanceId)
```
    Finish preloading for given topology version.
    
    Parameters:
    
    topVer - Topology version.
    
    rebalanceId - Rebalance id.

Interface GridCachePreloader

Method Summary

Method Detail

start

onKernalStop

onReconnected

onInitialExchangeComplete

rebalanceRequired

generateAssignments

addAssignments

startFuture

syncFuture

rebalanceFuture

needForceKeys

request

request

forceRebalance

handleSupplyMessage

handleDemandMessage

onTopologyChanged

dumpDebugInfo

pause

resume

timeout

batchesPrefetchCount

throttle

batchSize

finishPreloading