HHH-8682 org.hibernate.engine.spi.EntityKey consumes a lot of memory

hibernate-core/src/main/java/org/hibernate/engine/internal/EssentialEntityPersisterDetails.java

@@ -0,0 +1,70 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2013, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.engine.internal;
+
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.persister.entity.EntityEssentials;
+import org.hibernate.type.Type;
+
+
+public class EssentialEntityPersisterDetails implements EntityEssentials {
+
+	private final Type identifierType;
+	private final boolean isBatchLoadable;
+	private final String entityName;
+	private final String rootEntityName;
+
+	public EssentialEntityPersisterDetails(Type identifierType, boolean isBatchLoadable, String entityName, String rootEntityName) {
+		this.identifierType = identifierType;
+		this.isBatchLoadable = isBatchLoadable;
+		this.entityName = entityName;
+		this.rootEntityName = rootEntityName;
+	}
+
+	@Override
+	public Type getIdentifierType() {
+		return identifierType;
+	}
+
+	@Override
+	public boolean isBatchLoadable() {
+		return isBatchLoadable;
+	}
+
+	@Override
+	public String getEntityName() {
+		return entityName;
+	}
+
+	@Override
+	public String getRootEntityName() {
+		return rootEntityName;
+	}
+
+	@Override
+	public SessionFactoryImplementor getFactory() {
+		return null;
+	}
+
+}

hibernate-core/src/main/java/org/hibernate/engine/internal/StatefulPersistenceContext.java

@@ -1440,6 +1440,7 @@ public class StatefulPersistenceContext implements PersistenceContext {
 			LOG.trace( "Serializing persistent-context" );
 		}
 		final StatefulPersistenceContext rtn = new StatefulPersistenceContext( session );
+		SessionFactoryImplementor sfi = session==null ? null : session.getFactory();
 
 		// during deserialization, we need to reconnect all proxies and
 		// collections to this session, as well as the EntityEntry and
@@ -1457,7 +1458,7 @@ public class StatefulPersistenceContext implements PersistenceContext {
 			}
 			rtn.entitiesByKey = new HashMap<EntityKey,Object>( count < INIT_COLL_SIZE ? INIT_COLL_SIZE : count );
 			for ( int i = 0; i < count; i++ ) {
-				rtn.entitiesByKey.put( EntityKey.deserialize( ois, session ), ois.readObject() );
+				rtn.entitiesByKey.put( EntityKey.deserialize( ois, sfi ), ois.readObject() );
 			}
 
 			count = ois.readInt();
@@ -1483,7 +1484,7 @@ public class StatefulPersistenceContext implements PersistenceContext {
 					null
 			);
 			for ( int i = 0; i < count; i++ ) {
-				final EntityKey ek = EntityKey.deserialize( ois, session );
+				final EntityKey ek = EntityKey.deserialize( ois, sfi );
 				final Object proxy = ois.readObject();
 				if ( proxy instanceof HibernateProxy ) {
 					( (HibernateProxy) proxy ).getHibernateLazyInitializer().setSession( session );
@@ -1503,7 +1504,7 @@ public class StatefulPersistenceContext implements PersistenceContext {
 			}
 			rtn.entitySnapshotsByKey = new HashMap<EntityKey,Object>( count < INIT_COLL_SIZE ? INIT_COLL_SIZE : count );
 			for ( int i = 0; i < count; i++ ) {
-				rtn.entitySnapshotsByKey.put( EntityKey.deserialize( ois, session ), ois.readObject() );
+				rtn.entitySnapshotsByKey.put( EntityKey.deserialize( ois, sfi ), ois.readObject() );
 			}
 
 			rtn.entityEntryContext = EntityEntryContext.deserialize( ois, rtn );
@@ -1544,7 +1545,7 @@ public class StatefulPersistenceContext implements PersistenceContext {
 			}
 			rtn.nullifiableEntityKeys = new HashSet<EntityKey>();
 			for ( int i = 0; i < count; i++ ) {
-				rtn.nullifiableEntityKeys.add( EntityKey.deserialize( ois, session ) );
+				rtn.nullifiableEntityKeys.add( EntityKey.deserialize( ois, sfi ) );
 			}
 
 		}

hibernate-core/src/main/java/org/hibernate/engine/spi/EntityEntry.java

@@ -194,7 +194,7 @@ public final class EntityEntry implements Serializable {
 			if ( getId() == null ) {
 				throw new IllegalStateException( "cannot generate an EntityKey when id is null.");
 			}
-			cachedEntityKey = new EntityKey( getId(), getPersister(), tenantId );
+			cachedEntityKey = new EntityKey( getId(), getPersister() );
 		}
 		return cachedEntityKey;
 	}

hibernate-core/src/main/java/org/hibernate/engine/spi/EntityKey.java

@@ -1,7 +1,7 @@
 /*
  * Hibernate, Relational Persistence for Idiomatic Java
  *
- * Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
+ * Copyright (c) 2008-2013, Red Hat Inc. or third-party contributors as
  * indicated by the @author tags or express copyright attribution
  * statements applied by the authors.  All third-party contributions are
  * distributed under license by Red Hat Inc.
@@ -29,29 +29,31 @@ import java.io.ObjectOutputStream;
 import java.io.Serializable;
 
 import org.hibernate.AssertionFailure;
+import org.hibernate.engine.internal.EssentialEntityPersisterDetails;
 import org.hibernate.internal.util.compare.EqualsHelper;
+import org.hibernate.persister.entity.EntityEssentials;
 import org.hibernate.persister.entity.EntityPersister;
 import org.hibernate.pretty.MessageHelper;
 import org.hibernate.type.Type;
 
 /**
- * Uniquely identifies of an entity instance in a particular session by identifier.
+ * Uniquely identifies of an entity instance in a particular Session by identifier.
+ * Note that it's only safe to be used within the scope of a Session: it doesn't consider for example the tenantId
+ * as part of the equality definition.
  * <p/>
  * Information used to determine uniqueness consists of the entity-name and the identifier value (see {@link #equals}).
+ * <p/>
+ * Performance considerations: lots of instances of this type are created at runtime. Make sure each one is as small as possible
+ * by storing just the essential needed.
  *
  * @author Gavin King
+ * @author Sanne Grinovero
  */
 public final class EntityKey implements Serializable {
+
 	private final Serializable identifier;
-	private final String entityName;
-	private final String rootEntityName;
-	private final String tenantId;
-
 	private final int hashCode;
-
+	private final EntityEssentials persister;
-	private final Type identifierType;
-	private final boolean isBatchLoadable;
-	private final SessionFactoryImplementor factory;
 
 	/**
 	 * Construct a unique identifier for an entity class instance.
@@ -62,61 +64,42 @@ public final class EntityKey implements Serializable {
 	 *
 	 * @param id The entity id
 	 * @param persister The entity persister
-	 * @param tenantId The tenant identifier of the session to which this key belongs
 	 */
-	public EntityKey(Serializable id, EntityPersister persister, String tenantId) {
+	public EntityKey(Serializable id, EntityPersister persister) {
+		this.persister = persister;
 		if ( id == null ) {
 			throw new AssertionFailure( "null identifier" );
 		}
 		this.identifier = id;
-		this.rootEntityName = persister.getRootEntityName();
-		this.entityName = persister.getEntityName();
-		this.tenantId = tenantId;
-
-		this.identifierType = persister.getIdentifierType();
-		this.isBatchLoadable = persister.isBatchLoadable();
-		this.factory = persister.getFactory();
 		this.hashCode = generateHashCode();
 	}
 
 	/**
-	 * Used to reconstruct an EntityKey during deserialization.
+	 * Used to reconstruct an EntityKey during deserialization. Note that this constructor
+	 * is used only in very specific situations: the SessionFactory isn't actually available
+	 * and so both equals and hashcode implementations can't be implemented correctly.
 	 *
 	 * @param identifier The identifier value
-	 * @param rootEntityName The root entity name
+	 * @param fakePersister Is a placeholder for the EntityPersister, only providing essential methods needed for this purpose.
-	 * @param entityName The specific entity name
+	 * @param hashCode The hashCode needs to be provided as it can't be calculated correctly without the SessionFactory.
-	 * @param identifierType The type of the identifier value
-	 * @param batchLoadable Whether represented entity is eligible for batch loading
-	 * @param factory The session factory
-	 * @param tenantId The entity's tenant id (from the session that loaded it).
 	 */
-	private EntityKey(
+	private EntityKey(Serializable identifier, EntityEssentials fakePersister, int hashCode) {
-			Serializable identifier,
+		this.persister = fakePersister;
-			String rootEntityName,
+		if ( identifier == null ) {
-			String entityName,
+			throw new AssertionFailure( "null identifier" );
-			Type identifierType,
+		}
-			boolean batchLoadable,
-			SessionFactoryImplementor factory,
-			String tenantId) {
 		this.identifier = identifier;
-		this.rootEntityName = rootEntityName;
+		this.hashCode = hashCode;
-		this.entityName = entityName;
-		this.identifierType = identifierType;
-		this.isBatchLoadable = batchLoadable;
-		this.factory = factory;
-		this.tenantId = tenantId;
-		this.hashCode = generateHashCode();
 	}
 
 	private int generateHashCode() {
 		int result = 17;
-		result = 37 * result + rootEntityName.hashCode();
+		result = 37 * result + persister.getIdentifierType().getHashCode( identifier, persister.getFactory() );
-		result = 37 * result + identifierType.getHashCode( identifier, factory );
 		return result;
 	}
 
 	public boolean isBatchLoadable() {
-		return isBatchLoadable;
+		return persister.isBatchLoadable();
 	}
 
 	public Serializable getIdentifier() {
@@ -124,7 +107,7 @@ public final class EntityKey implements Serializable {
 	}
 
 	public String getEntityName() {
-		return entityName;
+		return persister.getEntityName();
 	}
 
 	@Override
@@ -132,14 +115,27 @@ public final class EntityKey implements Serializable {
 		if ( this == other ) {
 			return true;
 		}
-		if ( other == null || getClass() != other.getClass() ) {
+		if ( other == null || EntityKey.class != other.getClass() ) {
 			return false;
 		}
 
 		final EntityKey otherKey = (EntityKey) other;
-		return otherKey.rootEntityName.equals( this.rootEntityName )
+		return samePersistentType( otherKey )
-				&& identifierType.isEqual( otherKey.identifier, this.identifier, factory )
+				&& sameIdentifier( otherKey );
-				&& EqualsHelper.equals( tenantId, otherKey.tenantId );
+
+	}
+
+	private boolean sameIdentifier(final EntityKey otherKey) {
+		return persister.getIdentifierType().isEqual( otherKey.identifier, this.identifier, persister.getFactory() );
+	}
+
+	private boolean samePersistentType(final EntityKey otherKey) {
+		if ( otherKey.persister == persister ) {
+			return true;
+		}
+		else {
+			return EqualsHelper.equals( otherKey.persister.getRootEntityName(), persister.getRootEntityName() );
+		}
 	}
 
 	@Override
@@ -150,7 +146,7 @@ public final class EntityKey implements Serializable {
 	@Override
 	public String toString() {
 		return "EntityKey" +
-				MessageHelper.infoString( factory.getEntityPersister( entityName ), identifier, factory );
+				MessageHelper.infoString( this.persister, identifier, persister.getFactory() );
 	}
 
 	/**
@@ -162,12 +158,12 @@ public final class EntityKey implements Serializable {
 	 * @throws IOException Thrown by Java I/O
 	 */
 	public void serialize(ObjectOutputStream oos) throws IOException {
+		oos.writeObject( persister.getIdentifierType() );
+		oos.writeBoolean( isBatchLoadable() );
 		oos.writeObject( identifier );
-		oos.writeObject( rootEntityName );
+		oos.writeObject( persister.getEntityName() );
-		oos.writeObject( entityName );
+		oos.writeObject( persister.getRootEntityName() );
-		oos.writeObject( identifierType );
+		oos.writeInt( hashCode );
-		oos.writeBoolean( isBatchLoadable );
-		oos.writeObject( tenantId );
 	}
 
 	/**
@@ -175,24 +171,28 @@ public final class EntityKey implements Serializable {
 	 * Session/PersistenceContext for increased performance.
 	 *
 	 * @param ois The stream from which to read the entry.
-	 * @param session The session being deserialized.
+	 * @param sessionFactory The SessionFactory owning the Session being deserialized.
 	 *
 	 * @return The deserialized EntityEntry
 	 *
 	 * @throws IOException Thrown by Java I/O
 	 * @throws ClassNotFoundException Thrown by Java I/O
 	 */
-	public static EntityKey deserialize(
+	public static EntityKey deserialize(ObjectInputStream ois, SessionFactoryImplementor sessionFactory) throws IOException, ClassNotFoundException {
-			ObjectInputStream ois,
+		final Type identifierType = (Type) ois.readObject();
-			SessionImplementor session) throws IOException, ClassNotFoundException {
+		final boolean isBatchLoadable = ois.readBoolean();
-		return new EntityKey(
+		final Serializable id = (Serializable) ois.readObject();
-				(Serializable) ois.readObject(),
+		final String entityName = (String) ois.readObject();
-				(String) ois.readObject(),
+		final String rootEntityName = (String) ois.readObject();
-				(String) ois.readObject(),
+		final int hashCode = ois.readInt();
-				(Type) ois.readObject(),
+		if ( sessionFactory != null) {
-				ois.readBoolean(),
+			final EntityPersister entityPersister = sessionFactory.getEntityPersister( entityName );
-				(session == null ? null : session.getFactory()),
+			return new EntityKey(id, entityPersister);
-				(String) ois.readObject()
+		}
-		);
+		else {
+			//This version will produce an EntityKey which is technically unable to satisfy the equals contract!
+			final EntityEssentials fakePersister = new EssentialEntityPersisterDetails(identifierType, isBatchLoadable, entityName, rootEntityName);
+			return new EntityKey(id, fakePersister, hashCode);
+		}
 	}
 }

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

@@ -324,7 +324,7 @@ public abstract class AbstractSessionImpl
 
 	@Override
 	public EntityKey generateEntityKey(Serializable id, EntityPersister persister) {
-		return new EntityKey( id, persister, getTenantIdentifier() );
+		return new EntityKey( id, persister );
 	}
 
 	@Override

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

@@ -0,0 +1,52 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * Copyright (c) 2013, Red Hat Inc. or third-party contributors as
+ * indicated by the @author tags or express copyright attribution
+ * statements applied by the authors.  All third-party contributions are
+ * distributed under license by Red Hat Inc.
+ *
+ * This copyrighted material is made available to anyone wishing to use, modify,
+ * copy, or redistribute it subject to the terms and conditions of the GNU
+ * Lesser General Public License, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this distribution; if not, write to:
+ * Free Software Foundation, Inc.
+ * 51 Franklin Street, Fifth Floor
+ * Boston, MA  02110-1301  USA
+ */
+package org.hibernate.persister.entity;
+
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+import org.hibernate.type.Type;
+
+/**
+ * This the internal contract exposed by EntityPersister to EntityKey instances.
+ * The purpose is to keep the number of fields for EntityKey to a minimum amount
+ * and still be able to set it the properties listed here without having to create
+ * a complete EntityPersister implementation.
+ *
+ * @see org.hibernate.persister.entity.EntityPersister
+ * @see org.hibernate.engine.spi.EntityKey
+ *
+ * @author Sanne Grinovero
+ */
+public interface EntityEssentials {
+
+	Type getIdentifierType();
+
+	boolean isBatchLoadable();
+
+	String getEntityName();
+
+	String getRootEntityName();
+
+	SessionFactoryImplementor getFactory();
+
+}

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

@@ -63,7 +63,7 @@ import org.hibernate.type.VersionType;
  * @see org.hibernate.persister.spi.PersisterFactory
  * @see org.hibernate.persister.spi.PersisterClassResolver
  */
-public interface EntityPersister extends OptimisticCacheSource, EntityDefinition {
+public interface EntityPersister extends OptimisticCacheSource, EntityDefinition, EntityEssentials {
 
 	/**
 	 * The property name of the "special" identifier property in HQL

hibernate-core/src/main/java/org/hibernate/pretty/MessageHelper.java

@@ -29,6 +29,7 @@ import org.hibernate.collection.spi.PersistentCollection;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.engine.spi.SessionImplementor;
 import org.hibernate.persister.collection.CollectionPersister;
+import org.hibernate.persister.entity.EntityEssentials;
 import org.hibernate.persister.entity.EntityPersister;
 import org.hibernate.type.Type;
 
@@ -82,11 +83,11 @@ public final class MessageHelper {
 	 *
 	 * @param persister The persister for the entity
 	 * @param id The entity id value
-	 * @param factory The session factory
+	 * @param factory The session factory - Could be null!
 	 * @return An info string, in the form [FooBar#1]
 	 */
 	public static String infoString(
-			EntityPersister persister, 
+			EntityEssentials persister,
 			Object id, 
 			SessionFactoryImplementor factory) {
 		StringBuilder s = new StringBuilder();
@@ -110,7 +111,12 @@ public final class MessageHelper {
 				s.append( id );
 			}
 			else {
-				s.append( idType.toLoggableString( id, factory ) );
+				if ( factory != null ) {
+					s.append( idType.toLoggableString( id, factory ) );
+				}
+				else {
+					s.append( "<not loggable>" );
+				}
 			}
 		}
 		s.append( ']' );