Hibernate
/
hibernate-orm
mirror of https://github.com/hibernate/hibernate-orm
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

HHH-1775 - collection batch fetching 

Conflicts:

	hibernate-core/src/main/java/org/hibernate/engine/spi/BatchFetchQueue.java
This commit is contained in:
Steve Ebersole 2012-10-26 12:56:08 -05:00
parent 188e9f4587
commit a9bc598042
1 changed files with 142 additions and 90 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

226
hibernate-core/src/main/java/org/hibernate/engine/spi/BatchFetchQueue.java
View File

@ -25,15 +25,16 @@ package org.hibernate.engine.spi;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.Map;
import org.jboss.logging.Logger;
import org.hibernate.EntityMode;
import org.hibernate.cache.spi.CacheKey;
import org.hibernate.collection.spi.PersistentCollection;
import org.hibernate.internal.util.MarkerObject;
import org.hibernate.internal.util.collections.IdentityMap;
import org.hibernate.internal.CoreMessageLogger;
import org.hibernate.persister.collection.CollectionPersister;
import org.hibernate.persister.entity.EntityPersister;
@ -43,33 +44,35 @@ import org.hibernate.persister.entity.EntityPersister;
* can be re-used as a subquery for loading owned collections.
*
* @author Gavin King
* @author Steve Ebersole
* @author Guenther Demetz
*/
public class BatchFetchQueue {
private static final CoreMessageLogger LOG = Logger.getMessageLogger( CoreMessageLogger.class, BatchFetchQueue.class.getName() );
public static final Object MARKER = new MarkerObject( "MARKER" );
/**
* Defines a sequence of {@link EntityKey} elements that are currently
* elegible for batch-fetching.
* <p/>
* Even though this is a map, we only use the keys. A map was chosen in
* order to utilize a {@link LinkedHashMap} to maintain sequencing
* as well as uniqueness.
* <p/>
* TODO : this would be better as a SequencedReferenceSet, but no such beast exists!
*/
private final Map batchLoadableEntityKeys = new LinkedHashMap(8);
private final PersistenceContext context;
/**
* A map of {@link SubselectFetch subselect-fetch descriptors} keyed by the
* {@link EntityKey) against which the descriptor is registered.
*/
private final Map subselectsByEntityKey = new HashMap(8);
private final Map<EntityKey, SubselectFetch> subselectsByEntityKey = new HashMap<EntityKey, SubselectFetch>(8);
/**
* The owning persistence context.
* Used to hold information about the entities that are currently eligible for batch-fetching. Ultimately
* used by {@link #getEntityBatch} to build entity load batches.
* <p/>
* 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 final PersistenceContext context;
private final Map <String,LinkedHashSet<EntityKey>> batchLoadableEntityKeys = new HashMap <String,LinkedHashSet<EntityKey>>(8);
/**
* Used to hold information about the collections that are currently eligible for batch-fetching. Ultimately
* used by {@link #getCollectionBatch} to build collection load batches.
*/
private final Map<String, LinkedHashMap<CollectionEntry, PersistentCollection>> batchLoadableCollections =
new HashMap<String, LinkedHashMap <CollectionEntry, PersistentCollection>>(8);
/**
* Constructs a queue for the given context.
@ -88,6 +91,9 @@ public class BatchFetchQueue {
subselectsByEntityKey.clear();
}
// sub-select support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* Retrieve the fetch descriptor associated with the given entity key.
*
@ -96,7 +102,7 @@ public class BatchFetchQueue {
* this entity key.
*/
public SubselectFetch getSubselect(EntityKey key) {
return (SubselectFetch) subselectsByEntityKey.get(key);
return subselectsByEntityKey.get( key );
}
/**
@ -128,6 +134,9 @@ public class BatchFetchQueue {
subselectsByEntityKey.clear();
}
// entity batch support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* If an EntityKey represents a batch loadable entity, add
* it to the queue.
@ -140,7 +149,12 @@ public class BatchFetchQueue {
*/
public void addBatchLoadableEntityKey(EntityKey key) {
if ( key.isBatchLoadable() ) {
batchLoadableEntityKeys.put( key, MARKER );
LinkedHashSet<EntityKey> set = batchLoadableEntityKeys.get( key.getEntityName());
if (set == null) {
set = new LinkedHashSet<EntityKey>(8);
batchLoadableEntityKeys.put( key.getEntityName(), set);
}
set.add(key);
}
}
@ -150,71 +164,14 @@ public class BatchFetchQueue {
* if necessary
*/
public void removeBatchLoadableEntityKey(EntityKey key) {
if ( key.isBatchLoadable() ) batchLoadableEntityKeys.remove(key);
}
/**
* Get a batch of uninitialized collection keys for a given role
*
* @param collectionPersister The persister for the collection role.
* @param id A key that must be included in the batch fetch
* @param batchSize the maximum number of keys to return
* @return an array of collection keys, of length batchSize (padded with nulls)
*/
public Serializable[] getCollectionBatch(
final CollectionPersister collectionPersister,
final Serializable id,
final int batchSize) {
Serializable[] keys = new Serializable[batchSize];
keys[0] = id;
int i = 1;
//int count = 0;
int end = -1;
boolean checkForEnd = false;
// this only works because collection entries are kept in a sequenced
// map by persistence context (maybe we should do like entities and
// keep a separate sequences set...)
for ( Map.Entry<PersistentCollection,CollectionEntry> me :
IdentityMap.concurrentEntries( (Map<PersistentCollection,CollectionEntry>) context.getCollectionEntries() )) {
CollectionEntry ce = me.getValue();
PersistentCollection collection = me.getKey();
if ( !collection.wasInitialized() && ce.getLoadedPersister() == collectionPersister ) {
if ( checkForEnd && i == end ) {
return keys; //the first key found after the given key
}
//if ( end == -1 && count > batchSize*10 ) return keys; //try out ten batches, max
final boolean isEqual = collectionPersister.getKeyType().isEqual(
id,
ce.getLoadedKey(),
collectionPersister.getFactory()
);
if ( isEqual ) {
end = i;
//checkForEnd = false;
}
else if ( !isCached( ce.getLoadedKey(), collectionPersister ) ) {
keys[i++] = ce.getLoadedKey();
//count++;
}
if ( i == batchSize ) {
i = 1; //end of array, start filling again from start
if ( end != -1 ) {
checkForEnd = true;
if ( key.isBatchLoadable() ) {
LinkedHashSet<EntityKey> set = batchLoadableEntityKeys.get( key.getEntityName());
if (set != null) {
set.remove(key);
}
}
}
}
return keys; //we ran out of keys to try
}
/**
* Get a batch of unloaded identifiers for this class, using a slightly
* complex algorithm that tries to grab keys registered immediately after
@ -236,10 +193,11 @@ public class BatchFetchQueue {
int end = -1;
boolean checkForEnd = false;
Iterator iter = batchLoadableEntityKeys.keySet().iterator();
while ( iter.hasNext() ) {
EntityKey key = (EntityKey) iter.next();
if ( key.getEntityName().equals( persister.getEntityName() ) ) { //TODO: this needn't exclude subclasses...
// TODO: this needn't exclude subclasses...
LinkedHashSet<EntityKey> set = batchLoadableEntityKeys.get( persister.getEntityName() );
if ( set != null ) {
for ( EntityKey key : set ) {
if ( checkForEnd && i == end ) {
//the first id found after the given id
return ids;
@ -254,7 +212,9 @@ public class BatchFetchQueue {
}
if ( i == batchSize ) {
i = 1; // end of array, start filling again from start
if (end!=-1) checkForEnd = true;
if ( end != -1 ) {
checkForEnd = true;
}
}
}
}
@ -273,6 +233,98 @@ public class BatchFetchQueue {
return false;
}
// collection batch support ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/**
* If an CollectionEntry represents a batch loadable collection, add
* it to the queue.
*/
public void addBatchLoadableCollection(PersistentCollection collection, CollectionEntry ce) {
final CollectionPersister persister = ce.getLoadedPersister();
LinkedHashMap<CollectionEntry, PersistentCollection> map = batchLoadableCollections.get( persister.getRole() );
if ( map == null ) {
map = new LinkedHashMap<CollectionEntry, PersistentCollection>( 16 );
batchLoadableCollections.put( persister.getRole(), map );
}
map.put( ce, collection );
}
/**
* 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 removeBatchLoadableCollection(CollectionEntry ce) {
LinkedHashMap<CollectionEntry, PersistentCollection> map = batchLoadableCollections.get( ce.getLoadedPersister().getRole() );
if ( map != null ) {
map.remove( ce );
}
}
/**
* Get a batch of uninitialized collection keys for a given role
*
* @param collectionPersister The persister for the collection role.
* @param id A key that must be included in the batch fetch
* @param batchSize the maximum number of keys to return
* @return an array of collection keys, of length batchSize (padded with nulls)
*/
public Serializable[] getCollectionBatch(
final CollectionPersister collectionPersister,
final Serializable id,
final int batchSize) {
Serializable[] keys = new Serializable[batchSize];
keys[0] = id;
int i = 1;
int end = -1;
boolean checkForEnd = false;
final LinkedHashMap<CollectionEntry, PersistentCollection> map = batchLoadableCollections.get( collectionPersister.getRole() );
if ( map != null ) {
for ( Map.Entry<CollectionEntry, PersistentCollection> me : map.entrySet() ) {
final CollectionEntry ce = me.getKey();
final PersistentCollection collection = me.getValue();
if ( collection.wasInitialized() ) {
// should never happen
LOG.warn( "Encountered initialized collection in BatchFetchQueue, this should not happen." );
continue;
}
if ( checkForEnd && i == end ) {
return keys; //the first key found after the given key
}
final boolean isEqual = collectionPersister.getKeyType().isEqual(
id,
ce.getLoadedKey(),
collectionPersister.getFactory()
);
if ( isEqual ) {
end = i;
//checkForEnd = false;
}
else if ( !isCached( ce.getLoadedKey(), collectionPersister ) ) {
keys[i++] = ce.getLoadedKey();
//count++;
}
if ( i == batchSize ) {
i = 1; //end of array, start filling again from start
if ( end != -1 ) {
checkForEnd = true;
}
}
}
}
return keys; //we ran out of keys to try
}
private boolean isCached(Serializable collectionKey, CollectionPersister persister) {
if ( persister.hasCache() ) {
CacheKey cacheKey = context.getSession().generateCacheKey(