Package com.apple.foundationdb.record.provider.foundationdb.storestate

Class MetaDataVersionStampStoreStateCache

java.lang.Object

com.apple.foundationdb.record.provider.foundationdb.storestate.MetaDataVersionStampStoreStateCache

All Implemented Interfaces:

FDBRecordStoreStateCache

public class MetaDataVersionStampStoreStateCache
extends Object
implements FDBRecordStoreStateCache

An implementation of the FDBRecordStoreStateCache that uses the database's meta-data version-stamp key as the cache invalidation key. This will only cache the meta-data if it is "safe", that is, if the record store has marked its state as cacheable. This means that one should first set the state cacheability to true on any record store whose state one would want cached by calling FDBRecordStore.setStateCacheability(boolean). Then only those stores will be cached by this store state cache.

See Also:

FDBRecordStore.setStateCacheabilityAsync(boolean), FDBRecordContext.getMetaDataVersionStamp(IsolationLevel)

Method Summary

Modifier and Type	Method	Description
void	clear()	Remove all entries from the cache.
CompletableFuture<FDBRecordStoreStateCacheEntry>	get(FDBRecordStore recordStore, FDBRecordStoreBase.StoreExistenceCheck existenceCheck)	Load the record store state for the record store stored at the given location.
void	validateDatabase(FDBDatabase database)

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.apple.foundationdb.record.provider.foundationdb.storestate.FDBRecordStoreStateCache

validateContext

Method Detail

get

@Nonnull
public CompletableFuture<FDBRecordStoreStateCacheEntry> get(@Nonnull
                                                            FDBRecordStore recordStore,
                                                            @Nonnull
                                                            FDBRecordStoreBase.StoreExistenceCheck existenceCheck)

Description copied from interface: FDBRecordStoreStateCache

Load the record store state for the record store stored at the given location. If this information is available in the cache, it will be served from memory without communicating with the database. Otherwise, the information may require performing network and disk I/O. Note that the cache entry returned should be consistent with the view of the database as viewed by the transaction provided as input. The cache implementations are generally differentiated by the manner in which they invalidate data to ensure that the value returned is consistent with this contract.

This method should generally not be called by clients importing the Record Layer.

Specified by:

get in interface FDBRecordStoreStateCache

Parameters:

recordStore - the record store to load the store state of

existenceCheck - whether to error if the store does or does not exist

Returns:

a future that will complete with the cached store state

validateDatabase

public void validateDatabase(@Nonnull
                             FDBDatabase database)

Specified by:

validateDatabase in interface FDBRecordStoreStateCache

clear

public void clear()

Description copied from interface: FDBRecordStoreStateCache

Remove all entries from the cache.

Specified by:

clear in interface FDBRecordStoreStateCache