HHH-7572 - Develop API for load-by-multiple-ids

hibernate-core/src/main/java/org/hibernate/MultiIdentifierLoadAccess.java

@@ -38,6 +38,9 @@ public interface MultiIdentifierLoadAccess<T> {
 	 * to use a batch sizing strategy defined by the Dialect in use.  Any greater-than-one
 	 * value here will override that default behavior.  If giving an explicit value here,
 	 * care should be taken to not exceed the capabilities of of the underlying database.
+	 * <p/>
+	 * Note that overall a batch-size is considered a hint.  How the underlying loading
+	 * mechanism interprets that is completely up to that underlying loading mechanism.
 	 *
 	 * @param batchSize The batch size
 	 *

hibernate-core/src/main/java/org/hibernate/internal/SessionImpl.java

@@ -133,6 +133,7 @@ import org.hibernate.loader.custom.CustomQuery;
 import org.hibernate.loader.entity.DynamicBatchingEntityLoaderBuilder;
 import org.hibernate.persister.collection.CollectionPersister;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.persister.entity.MultiLoadOptions;
 import org.hibernate.persister.entity.OuterJoinLoadable;
 import org.hibernate.pretty.MessageHelper;
 import org.hibernate.procedure.ProcedureCall;
@@ -2771,7 +2772,7 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 		}
 	}
 
-	private class MultiIdentifierLoadAccessImpl<T> implements MultiIdentifierLoadAccess<T> {
+	private class MultiIdentifierLoadAccessImpl<T> implements MultiIdentifierLoadAccess<T>, MultiLoadOptions {
 		private final EntityPersister entityPersister;
 		private LockOptions lockOptions;
 		private CacheMode cacheMode;
@@ -2782,6 +2783,11 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 			this.entityPersister = entityPersister;
 		}
 
+		@Override
+		public LockOptions getLockOptions() {
+			return lockOptions;
+		}
+
 		@Override
 		public final MultiIdentifierLoadAccessImpl<T> with(LockOptions lockOptions) {
 			this.lockOptions = lockOptions;
@@ -2794,6 +2800,11 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 			return this;
 		}
 
+		@Override
+		public Integer getBatchSize() {
+			return batchSize;
+		}
+
 		@Override
 		public MultiIdentifierLoadAccess<T> withBatchSize(int batchSize) {
 			if ( batchSize < 1 ) {
@@ -2805,6 +2816,11 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 			return this;
 		}
 
+		@Override
+		public boolean isSessionCheckingEnabled() {
+			return sessionCheckingEnabled;
+		}
+
 		@Override
 		public MultiIdentifierLoadAccess<T> enableSessionCheck(boolean enabled) {
 			this.sessionCheckingEnabled = enabled;
@@ -2812,6 +2828,7 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 		}
 
 		@Override
+		@SuppressWarnings("unchecked")
 		public <K extends Serializable> List<T> multiLoad(K... ids) {
 			CacheMode sessionCacheMode = getCacheMode();
 			boolean cacheModeChanged = false;
@@ -2825,14 +2842,7 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 			}
 
 			try {
-				return DynamicBatchingEntityLoaderBuilder.INSTANCE.multiLoad(
+				return entityPersister.multiLoad( ids, SessionImpl.this, this );
-						(OuterJoinLoadable) entityPersister,
-						ids,
-						lockOptions,
-						batchSize,
-						sessionCheckingEnabled,
-						SessionImpl.this
-				);
 			}
 			finally {
 				if ( cacheModeChanged ) {
@@ -2843,6 +2853,7 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 		}
 
 		@Override
+		@SuppressWarnings("unchecked")
 		public <K extends Serializable> List<T> multiLoad(List<K> ids) {
 			CacheMode sessionCacheMode = getCacheMode();
 			boolean cacheModeChanged = false;
@@ -2856,14 +2867,7 @@ public final class SessionImpl extends AbstractSessionImpl implements EventSourc
 			}
 
 			try {
-				return DynamicBatchingEntityLoaderBuilder.INSTANCE.multiLoad(
+				return entityPersister.multiLoad( ids.toArray( new Serializable[ ids.size() ] ), SessionImpl.this, this );
-						(OuterJoinLoadable) entityPersister,
-						ids.toArray( new Serializable[ ids.size() ] ),
-						lockOptions,
-						batchSize,
-						sessionCheckingEnabled,
-						SessionImpl.this
-				);
 			}
 			finally {
 				if ( cacheModeChanged ) {

hibernate-core/src/main/java/org/hibernate/loader/entity/DynamicBatchingEntityLoaderBuilder.java

@@ -29,6 +29,7 @@ import org.hibernate.internal.util.StringHelper;
 import org.hibernate.internal.util.collections.ArrayHelper;
 import org.hibernate.internal.util.collections.CollectionHelper;
 import org.hibernate.loader.spi.AfterLoadAction;
+import org.hibernate.persister.entity.MultiLoadOptions;
 import org.hibernate.persister.entity.OuterJoinLoadable;
 import org.hibernate.pretty.MessageHelper;
 import org.hibernate.type.Type;
@@ -47,26 +48,23 @@ public class DynamicBatchingEntityLoaderBuilder extends BatchingEntityLoaderBuil
 	public static final DynamicBatchingEntityLoaderBuilder INSTANCE = new DynamicBatchingEntityLoaderBuilder();
 
 	@SuppressWarnings("unchecked")
-	public <T, K extends Serializable> List<T> multiLoad(
+	public List multiLoad(
 			OuterJoinLoadable persister,
-			K[] ids,
+			Serializable[] ids, SessionImplementor session,
-			LockOptions lockOptions,
+			MultiLoadOptions loadOptions) {
-			Integer explicitBatchSize,
+		List result = CollectionHelper.arrayList( ids.length );
-			boolean sessionCheckingEnabled,
-			SessionImplementor session) {
-		List<T> result = CollectionHelper.arrayList( ids.length );
 
-		if ( sessionCheckingEnabled ) {
+		if ( loadOptions.isSessionCheckingEnabled() ) {
 			// the user requested that we exclude ids corresponding to already managed
 			// entities from the generated load SQL.  So here we will iterate all
 			// incoming id values and see whether it corresponds to an existing
 			// entity associated with the PC - if it does we add it to the result
 			// list immediately and remove its id from the group of ids to load.
 			boolean foundAnyManagedEntities = false;
-			final List<K> nonManagedIds = new ArrayList<K>();
+			final List<Serializable> nonManagedIds = new ArrayList<Serializable>();
-			for ( K id : ids ) {
+			for ( Serializable id : ids ) {
 				final EntityKey entityKey = new EntityKey( id, persister );
-				final T managedEntity = (T) session.getPersistenceContext().getEntity( entityKey );
+				final Object managedEntity = session.getPersistenceContext().getEntity( entityKey );
 				if ( managedEntity != null ) {
 					foundAnyManagedEntities = true;
 					result.add( managedEntity );
@@ -85,7 +83,7 @@ public class DynamicBatchingEntityLoaderBuilder extends BatchingEntityLoaderBuil
 					// over-write the ids to be loaded with the collection of
 					// just non-managed ones
 					ids = nonManagedIds.toArray(
-							(K[]) Array.newInstance(
+							(Serializable[]) Array.newInstance(
 									ids.getClass().getComponentType(),
 									nonManagedIds.size()
 							)
@@ -94,16 +92,14 @@ public class DynamicBatchingEntityLoaderBuilder extends BatchingEntityLoaderBuil
 			}
 		}
 
-
+		final LockOptions lockOptions = (loadOptions.getLockOptions() == null)
-		if ( lockOptions == null ) {
+				? new LockOptions( LockMode.NONE )
-			lockOptions = new LockOptions( LockMode.NONE );
+				: loadOptions.getLockOptions();
-		}
 
 		int numberOfIdsLeft = ids.length;
-
 		final int maxBatchSize;
-		if ( explicitBatchSize != null && explicitBatchSize > 0 ) {
+		if ( loadOptions.getBatchSize() != null && loadOptions.getBatchSize() > 0 ) {
-			maxBatchSize = explicitBatchSize;
+			maxBatchSize = loadOptions.getBatchSize();
 		}
 		else {
 			maxBatchSize = session.getFactory().getDialect().getDefaultBatchLoadSizingStrategy().determineOptimalBatchLoadSize(

hibernate-core/src/main/java/org/hibernate/persister/entity/AbstractEntityPersister.java

@@ -79,6 +79,7 @@ import org.hibernate.id.insert.InsertGeneratedIdentifierDelegate;
 import org.hibernate.internal.CoreLogging;
 import org.hibernate.internal.CoreMessageLogger;
 import org.hibernate.internal.FilterHelper;
+import org.hibernate.internal.SessionImpl;
 import org.hibernate.internal.util.StringHelper;
 import org.hibernate.internal.util.collections.ArrayHelper;
 import org.hibernate.jdbc.Expectation;
@@ -86,6 +87,7 @@ import org.hibernate.jdbc.Expectations;
 import org.hibernate.jdbc.TooManyRowsAffectedException;
 import org.hibernate.loader.entity.BatchingEntityLoaderBuilder;
 import org.hibernate.loader.entity.CascadeEntityLoader;
+import org.hibernate.loader.entity.DynamicBatchingEntityLoaderBuilder;
 import org.hibernate.loader.entity.EntityLoader;
 import org.hibernate.loader.entity.UniqueEntityLoader;
 import org.hibernate.mapping.Column;
@@ -3989,6 +3991,16 @@ public abstract class AbstractEntityPersister
 		return loader.load( id, optionalObject, session, lockOptions );
 	}
 
+	@Override
+	public List multiLoad(Serializable[] ids, SessionImplementor session, MultiLoadOptions loadOptions) {
+		return DynamicBatchingEntityLoaderBuilder.INSTANCE.multiLoad(
+				this,
+				ids,
+				session,
+				loadOptions
+		);
+	}
+
 	public void registerAffectingFetchProfile(String fetchProfileName) {
 		affectingFetchProfileNames.add( fetchProfileName );
 	}

hibernate-core/src/main/java/org/hibernate/persister/entity/EntityPersister.java

@@ -7,8 +7,8 @@
 package org.hibernate.persister.entity;
 
 import java.io.Serializable;
+import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 import org.hibernate.EntityMode;
 import org.hibernate.HibernateException;
@@ -364,6 +364,17 @@ public interface EntityPersister extends OptimisticCacheSource, EntityDefinition
 	public Object load(Serializable id, Object optionalObject, LockOptions lockOptions, SessionImplementor session)
 	throws HibernateException;
 
+	/**
+	 * Performs a load of multiple entities (of this type) by identifier simultaneously.
+	 *
+	 * @param ids The identifiers to load
+	 * @param session The originating Sesison
+	 * @param loadOptions The options for loading
+	 *
+	 * @return The loaded, matching entities
+	 */
+	List multiLoad(Serializable[] ids, SessionImplementor session, MultiLoadOptions loadOptions);
+
 	/**
 	 * Do a version check (optional operation)
 	 */

hibernate-core/src/main/java/org/hibernate/persister/entity/MultiLoadOptions.java

@@ -0,0 +1,22 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.persister.entity;
+
+import org.hibernate.LockOptions;
+
+/**
+ * Encapsulation of the options for performing a load by multiple identifiers.
+ *
+ * @author Steve Ebersole
+ */
+public interface MultiLoadOptions {
+	boolean isSessionCheckingEnabled();
+
+	LockOptions getLockOptions();
+
+	Integer getBatchSize();
+}

hibernate-core/src/test/java/org/hibernate/test/cfg/persister/GoofyPersisterClassProvider.java

@@ -9,7 +9,9 @@ package org.hibernate.test.cfg.persister;
 import java.io.Serializable;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.util.Collections;
 import java.util.Comparator;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -40,6 +42,7 @@ import org.hibernate.metadata.ClassMetadata;
 import org.hibernate.metadata.CollectionMetadata;
 import org.hibernate.persister.collection.CollectionPersister;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.persister.entity.MultiLoadOptions;
 import org.hibernate.persister.spi.PersisterClassResolver;
 import org.hibernate.persister.spi.PersisterCreationContext;
 import org.hibernate.persister.walking.spi.AttributeDefinition;
@@ -267,6 +270,12 @@ public class GoofyPersisterClassProvider implements PersisterClassResolver {
 			return null;
 		}
 
+		@Override
+		public List multiLoad(
+				Serializable[] ids, SessionImplementor session, MultiLoadOptions loadOptions) {
+			return Collections.emptyList();
+		}
+
 		@Override
 		public void lock(Serializable id, Object version, Object object, LockMode lockMode, SessionImplementor session) {
 		}

hibernate-core/src/test/java/org/hibernate/test/legacy/CustomPersister.java

@@ -7,10 +7,11 @@
 package org.hibernate.test.legacy;
 
 import java.io.Serializable;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.Hashtable;
+import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 import org.hibernate.EntityMode;
 import org.hibernate.HibernateException;
@@ -43,6 +44,7 @@ import org.hibernate.internal.util.compare.EqualsHelper;
 import org.hibernate.mapping.PersistentClass;
 import org.hibernate.metadata.ClassMetadata;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.persister.entity.MultiLoadOptions;
 import org.hibernate.persister.spi.PersisterCreationContext;
 import org.hibernate.persister.walking.spi.AttributeDefinition;
 import org.hibernate.persister.walking.spi.EntityIdentifierDefinition;
@@ -304,6 +306,11 @@ public class CustomPersister implements EntityPersister {
 		return load(id, optionalObject, lockOptions.getLockMode(), session);
 	}
 
+	@Override
+	public List multiLoad(Serializable[] ids, SessionImplementor session, MultiLoadOptions loadOptions) {
+		return Collections.emptyList();
+	}
+
 	/**
 	 * @see EntityPersister#load(Serializable, Object, LockMode, SessionImplementor)
 	 */

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/ejb3configuration/PersisterClassProviderTest.java

@@ -8,7 +8,9 @@ package org.hibernate.jpa.test.ejb3configuration;
 
 import java.io.Serializable;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Comparator;
+import java.util.List;
 import java.util.Map;
 import javax.persistence.EntityManagerFactory;
 import javax.persistence.PersistenceException;
@@ -40,6 +42,7 @@ import org.hibernate.mapping.PersistentClass;
 import org.hibernate.metadata.ClassMetadata;
 import org.hibernate.persister.collection.CollectionPersister;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.persister.entity.MultiLoadOptions;
 import org.hibernate.persister.internal.PersisterClassResolverInitiator;
 import org.hibernate.persister.spi.PersisterClassResolver;
 import org.hibernate.persister.spi.PersisterCreationContext;
@@ -303,6 +306,11 @@ public class PersisterClassProviderTest {
 			return null;
 		}
 
+		@Override
+		public List multiLoad(Serializable[] ids, SessionImplementor session, MultiLoadOptions loadOptions) {
+			return Collections.emptyList();
+		}
+
 		@Override
 		public void lock(Serializable id, Object version, Object object, LockMode lockMode, SessionImplementor session) {
 		}