org.hibernate.engine
Class BatchFetchQueue

java.lang.Object
  org.hibernate.engine.BatchFetchQueue

public class BatchFetchQueue

extends Object

Tracks entity and collection keys that are available for batch fetching, and the queries which were used to load entities, which can be re-used as a subquery for loading owned collections.

Author:

Gavin King

Field Summary

static Object

MARKER

Constructor Summary

BatchFetchQueue(PersistenceContext context)

Method Summary

void	addBatchLoadableEntityKey(EntityKey key) If an EntityKey represents a batch loadable entity, add it to the queue.
void	addSubselect(EntityKey key, SubselectFetch subquery)
void	clear()
void	clearSubselects()
Serializable[]	getCollectionBatch(CollectionPersister collectionPersister, Serializable id, int batchSize, EntityMode entityMode) Get a batch of uninitialized collection keys for this role
Serializable[]	getEntityBatch(EntityPersister persister, Serializable id, int batchSize, EntityMode entityMode) 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.
SubselectFetch	getSubselect(EntityKey key)
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
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)

Methods inherited from class java.lang.Object

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

Field Detail

MARKER

public static final Object MARKER

Constructor Detail

BatchFetchQueue

public BatchFetchQueue(PersistenceContext context)

Method Detail

clear

public void clear()

getSubselect

public SubselectFetch getSubselect(EntityKey key)

addSubselect

public void addSubselect(EntityKey key,
                         SubselectFetch subquery)

clearSubselects

public void clearSubselects()

removeBatchLoadableEntityKey

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

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)

addBatchLoadableEntityKey

public void addBatchLoadableEntityKey(EntityKey key)

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

getCollectionBatch

public Serializable[] getCollectionBatch(CollectionPersister collectionPersister,
                                         Serializable id,
                                         int batchSize,
                                         EntityMode entityMode)

Get a batch of uninitialized collection keys for this role

Parameters:

collectionPersister - the collection role

id - a key that must be included

batchSize - the maximum number of keys to return

Returns:

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

getEntityBatch

public Serializable[] getEntityBatch(EntityPersister persister,
                                     Serializable id,
                                     int batchSize,
                                     EntityMode entityMode)

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.

Parameters:

id - an identifier that must be included

batchSize - the maximum number of keys to return

Returns:

an array of identifiers, of length batchSize (padded with nulls)