Hibernate ORM - hibernate-core 6.4.4.Final · org.hibernate.engine.spi.BatchFetchQueue

Modifier and Type	Field and Description
private @Nullable Map<String, LinkedHashMap<CollectionEntry, PersistentCollection<?>>>	batchLoadableCollections Used to hold information about the collections that are currently eligible for batch-fetching.
private @Nullable Map<String, LinkedHashSet<EntityKey>>	batchLoadableEntityKeys Used to hold information about the entities that are currently eligible for batch-fetching.
private final PersistenceContext	context
private static final Logger	LOG
private @Nullable Map<EntityKey, SubselectFetch>	subselectsByEntityKey A map of `subselect-fetch descriptors` keyed by the `EntityKey` against which the descriptor is registered.

Access	Constructor and Description
public	BatchFetchQueue(PersistenceContext The owning context. context) Constructs a queue for the given context.

Method Summary

Modifier and Type	Method and Description
public void	addBatchLoadableCollection(PersistentCollection<?> collection, CollectionEntry ce) If a CollectionEntry represents a batch loadable collection, add it to the queue.
public void	addBatchLoadableEntityKey(EntityKey key) If an EntityKey represents a batch loadable entity, add it to the queue.
public void	addSubselect(EntityKey The entity for which to register the subselect fetch. key, SubselectFetch The fetch descriptor. subquery) Adds a subselect fetch descriptor for the given entity key.
public void	clear() Clears all entries from this fetch queue.
public <T> void	collectBatchLoadableCollectionKeys(int batchSize, IndexedConsumer<T> collector, @NonNull T keyBeingLoaded, PluralAttributeMapping pluralAttributeMapping) A "collector" form of `getCollectionBatch`.
public <T> void	collectBatchLoadableEntityIds(final int domainBatchSize, IndexedConsumer<T> collector, final @NonNull T loadingId, final EntityMappingType entityDescriptor) A "collector" form of `getBatchLoadableEntityIds`.
public boolean	containsEntityKey(EntityKey key) Intended for test usage.
public Object[]	getBatchLoadableEntityIds(final EntityMappingType entityDescriptor, final Object loadingId, final int maxBatchSize) Get a batch of unloaded identifiers for this class, using a slightly complex algorithm that tries to grab keys registered immediately after the given key.
public Object[]	Returns: an array of collection keys, of length batchSize (padded with nulls) getCollectionBatch(final CollectionPersister The persister for the collection role. collectionPersister, final Object A key that must be included in the batch fetch id, final int the maximum number of keys to return batchSize) Get a batch of uninitialized collection keys for a given role
public SharedSessionContractImplementor	getSession()
public @Nullable SubselectFetch	Returns: The fetch descriptor; may return null if no subselect fetch queued for this entity key. getSubselect(EntityKey The entity key for which to locate any defined subselect fetch. key) Retrieve the fetch descriptor associated with the given entity key.
private boolean	isCached(EntityKey entityKey, EntityPersister persister)
private boolean	isCached(Object collectionKey, CollectionPersister persister)
public void	removeBatchLoadableCollection(CollectionEntry ce) After a collection was initialized or evicted, we don't need to batch fetch it anymore, remove it from the queue if necessary
public void	removeBatchLoadableEntityKey(EntityKey key) After evicting or deleting or loading an entity, we don't need to batch fetch it anymore, remove it from the queue if necessary
public void	removeSubselect(EntityKey key) After evicting or deleting an entity, we don't need to know the query that was used to load it anymore (don't call this after loading the entity, since we might still need to load its collections)

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

batchLoadableCollections	back to summary
private @Nullable Map<String, LinkedHashMap<CollectionEntry, PersistentCollection<?>>> batchLoadableCollections Used to hold information about the collections that are currently eligible for batch-fetching. Ultimately used by `getCollectionBatch` to build collection load batches.

batchLoadableEntityKeys back to summary

batchLoadableEntityKeys	back to summary
private @Nullable Map<String, LinkedHashSet<EntityKey>> batchLoadableEntityKeys Used to hold information about the entities that are currently eligible for batch-fetching. Ultimately used by `getBatchLoadableEntityIds` to build entity load batches. A Map structure is used to segment the keys by entity type since loading can only be done for a particular entity type at a time.

private @Nullable Map<String, LinkedHashSet<EntityKey>> batchLoadableEntityKeys

Used to hold information about the entities that are currently eligible for batch-fetching. Ultimately used by getBatchLoadableEntityIds to build entity load batches.

A Map structure is used to segment the keys by entity type since loading can only be done for a particular entity type at a time.

context	back to summary
private final PersistenceContext context

LOG	back to summary
private static final Logger LOG

subselectsByEntityKey	back to summary
private @Nullable Map<EntityKey, SubselectFetch> subselectsByEntityKey A map of `subselect-fetch descriptors` keyed by the `EntityKey` against which the descriptor is registered.

Constructor Detail

BatchFetchQueue	back to summary
public BatchFetchQueue(PersistenceContext context) Constructs a queue for the given context. Parameters context:PersistenceContext The owning context.

BatchFetchQueue

back to summary

public BatchFetchQueue(PersistenceContext context)

Constructs a queue for the given context.

Parameters

context:PersistenceContext: The owning context.

Method Detail

addBatchLoadableCollection	back to summary
public void addBatchLoadableCollection(PersistentCollection<?> collection, CollectionEntry ce) If a CollectionEntry represents a batch loadable collection, add it to the queue.

addBatchLoadableEntityKey back to summary

addBatchLoadableEntityKey	back to summary
public void addBatchLoadableEntityKey(EntityKey key) If an EntityKey represents a batch loadable entity, add it to the queue. Note that the contract here is such that any key passed in should previously have been been checked for existence within the `PersistenceContext`; failure to do so may cause the referenced entity to be included in a batch even though it is already associated with the `PersistenceContext`.

public void addBatchLoadableEntityKey(EntityKey key)

If an EntityKey represents a batch loadable entity, add it to the queue.

Note that the contract here is such that any key passed in should previously have been been checked for existence within the PersistenceContext; failure to do so may cause the referenced entity to be included in a batch even though it is already associated with the PersistenceContext.

addSubselect	back to summary
public void addSubselect(EntityKey key, SubselectFetch subquery) Adds a subselect fetch descriptor for the given entity key. Parameters key:EntityKey The entity for which to register the subselect fetch. subquery:SubselectFetch The fetch descriptor.

addSubselect

back to summary

public void addSubselect(EntityKey key, SubselectFetch subquery)

Adds a subselect fetch descriptor for the given entity key.

Parameters

key:EntityKey: The entity for which to register the subselect fetch.
subquery:SubselectFetch: The fetch descriptor.

clear	back to summary
public void clear() Clears all entries from this fetch queue. Called after flushing or clearing the session.

clear

back to summary

public void clear()

Clears all entries from this fetch queue.

Called after flushing or clearing the session.

collectBatchLoadableCollectionKeys back to summary

collectBatchLoadableCollectionKeys	back to summary
public <T> void collectBatchLoadableCollectionKeys(int batchSize, IndexedConsumer<T> collector, @NonNull T keyBeingLoaded, PluralAttributeMapping pluralAttributeMapping) A "collector" form of `getCollectionBatch`. Useful in cases where we want a specially created array/container - allows creation of concretely typed array for ARRAY param binding to ensure the driver does not need to cast/copy the values array.

public <T> void collectBatchLoadableCollectionKeys(int batchSize, IndexedConsumer<T> collector, @NonNull T keyBeingLoaded, PluralAttributeMapping pluralAttributeMapping)

A "collector" form of getCollectionBatch. Useful in cases where we want a specially created array/container - allows creation of concretely typed array for ARRAY param binding to ensure the driver does not need to cast/copy the values array.

collectBatchLoadableEntityIds back to summary

collectBatchLoadableEntityIds	back to summary
public <T> void collectBatchLoadableEntityIds(final int domainBatchSize, IndexedConsumer<T> collector, final @NonNull T loadingId, final EntityMappingType entityDescriptor) A "collector" form of `getBatchLoadableEntityIds`. Useful in cases where we want a specially created array/container - allows creation of concretely typed array for ARRAY param binding to ensure the driver does not need to cast/copy the values array.

public <T> void collectBatchLoadableEntityIds(final int domainBatchSize, IndexedConsumer<T> collector, final @NonNull T loadingId, final EntityMappingType entityDescriptor)

A "collector" form of getBatchLoadableEntityIds. Useful in cases where we want a specially created array/container - allows creation of concretely typed array for ARRAY param binding to ensure the driver does not need to cast/copy the values array.

containsEntityKey	back to summary
public boolean containsEntityKey(EntityKey key) Intended for test usage. Really has no use-case in Hibernate proper.

getBatchLoadableEntityIds	back to summary
public Object[] getBatchLoadableEntityIds(final EntityMappingType entityDescriptor, final Object loadingId, final int maxBatchSize) Get a batch of unloaded identifiers for this class, using a slightly complex algorithm that tries to grab keys registered immediately after the given key.

getCollectionBatch	back to summary
public Object[] getCollectionBatch(final CollectionPersister collectionPersister, final Object id, final int batchSize) Get a batch of uninitialized collection keys for a given role Parameters collectionPersister:CollectionPersister The persister for the collection role. id:Object A key that must be included in the batch fetch batchSize:int the maximum number of keys to return Returns:Object[] an array of collection keys, of length batchSize (padded with nulls)

getCollectionBatch

back to summary

public Object[] getCollectionBatch(final CollectionPersister collectionPersister, final Object id, final int batchSize)

Get a batch of uninitialized collection keys for a given role

Parameters

collectionPersister:CollectionPersister: The persister for the collection role.
id:Object: A key that must be included in the batch fetch
batchSize:int: the maximum number of keys to return

Returns:Object[]

an array of collection keys, of length batchSize (padded with nulls)

getSession	back to summary
public SharedSessionContractImplementor getSession()

getSubselect	back to summary
public @Nullable SubselectFetch getSubselect(EntityKey key) Retrieve the fetch descriptor associated with the given entity key. Parameters key:EntityKey The entity key for which to locate any defined subselect fetch. Returns:@Nullable SubselectFetch The fetch descriptor; may return null if no subselect fetch queued for this entity key.

getSubselect

back to summary

public @Nullable SubselectFetch getSubselect(EntityKey key)

Retrieve the fetch descriptor associated with the given entity key.

Parameters

key:EntityKey: The entity key for which to locate any defined subselect fetch.

Returns:@Nullable SubselectFetch

The fetch descriptor; may return null if no subselect fetch queued for this entity key.

isCached	back to summary
private boolean isCached(EntityKey entityKey, EntityPersister persister)

isCached	back to summary
private boolean isCached(Object collectionKey, CollectionPersister persister)

removeBatchLoadableCollection	back to summary
public void removeBatchLoadableCollection(CollectionEntry ce) After a collection was initialized or evicted, we don't need to batch fetch it anymore, remove it from the queue if necessary

removeBatchLoadableEntityKey	back to summary
public void removeBatchLoadableEntityKey(EntityKey key) After evicting or deleting or loading an entity, we don't need to batch fetch it anymore, remove it from the queue if necessary

removeSubselect	back to summary
public void removeSubselect(EntityKey key) After evicting or deleting an entity, we don't need to know the query that was used to load it anymore (don't call this after loading the entity, since we might still need to load its collections)

public Class BatchFetchQueue

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail