HHH-19535 Interceptor and merge()

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

@@ -378,7 +378,7 @@
 	 * @param entity The entity instance being deleted
 	 * @param id The identifier of the entity
 	 * @param state The entity state
-	 * @param propertyNames The names of the entity properties.
+	 * @param propertyNames The names of the entity properties
 	 * @param propertyTypes The types of the entity properties
 	 *
 	 * @see StatelessSession#update(Object)
@@ -391,7 +391,7 @@
 	 * @param entity The entity instance being deleted
 	 * @param id The identifier of the entity
 	 * @param state The entity state
-	 * @param propertyNames The names of the entity properties.
+	 * @param propertyNames The names of the entity properties
 	 * @param propertyTypes The types of the entity properties
 	 *
 	 * @see StatelessSession#upsert(String, Object)
@@ -403,10 +403,49 @@
 	 *
 	 * @param entity The entity instance being deleted
 	 * @param id The identifier of the entity
-	 * @param propertyNames The names of the entity properties.
+	 * @param propertyNames The names of the entity properties
 	 * @param propertyTypes The types of the entity properties
 	 *
 	 * @see StatelessSession#delete(Object)
 	 */
 	default void onDelete(Object entity, Object id, String[] propertyNames, Type[] propertyTypes) {}
+
+	/**
+	 * Called before copying the state of a merged entity to a managed entity
+	 * belonging to the persistence context of a stateful {@link Session}.
+	 * <p>
+	 * The interceptor may modify the {@code state}.
+	 *
+	 * @param entity The entity passed to {@code merge()}
+	 * @param state The state of the entity passed to {@code merge()}
+	 * @param propertyNames The names of the entity properties
+	 * @param propertyTypes The types of the entity properties
+	 *
+	 * @since 7.1
+	 */
+	@Incubating
+	default void preMerge(Object entity, Object[] state, String[] propertyNames, Type[] propertyTypes) {}
+
+	/**
+	 * Called after copying the state of a merged entity to a managed entity
+	 * belonging to the persistence context of a stateful {@link Session}.
+	 * <p>
+	 * Modification of the {@code sourceState} or {@code targetState} has no effect.
+	 *
+	 * @param source The entity passed to {@code merge()}
+	 * @param target The target managed entity
+	 * @param id The identifier of the managed entity
+	 * @param targetState The copied state already assigned to the target managed entity
+	 * @param originalState The original state of the target managed entity before assignment of the copied state,
+	 * or {@code null} if the target entity is a new instance
+	 * @param propertyNames The names of the entity properties
+	 * @param propertyTypes The types of the entity properties
+	 *
+	 * @since 7.1
+	 */
+	@Incubating
+	default void postMerge(
+			Object source, Object target, Object id,
+			Object[] targetState, Object[] originalState,
+			String[] propertyNames, Type[] propertyTypes) {}
 }

hibernate-core/src/main/java/org/hibernate/boot/registry/selector/internal/StrategySelectorImpl.java

@@ -157,13 +157,10 @@ public <T> T resolveStrategy(
 			return strategy.cast( strategyReference );
 		}
 
-		final Class<? extends T> implementationClass;
-		if ( strategyReference instanceof Class ) {
-			implementationClass = (Class<T>) strategyReference;
-		}
-		else {
-			implementationClass = selectStrategyImplementor( strategy, strategyReference.toString() );
-		}
+		final Class<? extends T> implementationClass =
+				strategyReference instanceof Class
+						? (Class<? extends T>) strategyReference
+						: selectStrategyImplementor( strategy, strategyReference.toString() );
 
 		try {
 			return creator.create( implementationClass );

hibernate-core/src/main/java/org/hibernate/event/internal/DefaultMergeEventListener.java

@@ -8,6 +8,7 @@
 
 import org.hibernate.AssertionFailure;
 import org.hibernate.HibernateException;
+import org.hibernate.Interceptor;
 import org.hibernate.ObjectDeletedException;
 import org.hibernate.StaleObjectStateException;
 import org.hibernate.WrongClassException;
@@ -25,7 +26,6 @@
 import org.hibernate.engine.spi.PersistentAttributeInterceptor;
 import org.hibernate.engine.spi.SelfDirtinessTracker;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
-import org.hibernate.engine.spi.SessionImplementor;
 import org.hibernate.event.spi.EntityCopyObserver;
 import org.hibernate.event.spi.EventSource;
 import org.hibernate.event.spi.MergeContext;
@@ -220,7 +220,7 @@ private void merge(MergeEvent event, MergeContext copiedAlready, Object entity)
 							)
 					);
 					source.getActionQueue().unScheduleUnloadedDeletion( entity );
-					entityIsDetached(event, copiedId, originalId, copiedAlready);
+					entityIsDetached( event, copiedId, originalId, copiedAlready );
 					break;
 				}
 				throw new ObjectDeletedException( "deleted instance passed to merge",
@@ -274,7 +274,7 @@ protected void entityIsPersistent(MergeEvent event, MergeContext copyCache) {
 		final EntityPersister persister = source.getEntityPersister( event.getEntityName(), entity );
 		copyCache.put( entity, entity, true );  //before cascade!
 		cascadeOnMerge( source, persister, entity, copyCache );
-		copyValues( persister, entity, entity, source, copyCache );
+		TypeHelper.replace( persister, entity, source, entity, copyCache );
 		event.setResult( entity );
 	}
 
@@ -283,27 +283,55 @@ protected void entityIsTransient(MergeEvent event, Object id, MergeContext copyC
 
 		final Object entity = event.getEntity();
 		final EventSource session = event.getSession();
+		final Interceptor interceptor = session.getInterceptor();
 		final String entityName = event.getEntityName();
 		final EntityPersister persister = session.getEntityPersister( entityName, entity );
+		final String[] propertyNames = persister.getPropertyNames();
+		final Type[] propertyTypes = persister.getPropertyTypes();
 		final Object copy = copyEntity( copyCache, entity, session, persister, id );
 
 		// cascade first, so that all unsaved objects get their
 		// copy created before we actually copy
 		//cascadeOnMerge(event, persister, entity, copyCache, Cascades.CASCADE_BEFORE_MERGE);
 		super.cascadeBeforeSave( session, persister, entity, copyCache );
-		copyValues( persister, entity, copy, session, copyCache, ForeignKeyDirection.FROM_PARENT );
+
+		final Object[] sourceValues = persister.getValues( entity );
+		interceptor.preMerge( entity, sourceValues, propertyNames, propertyTypes );
+		final Object[] copiedValues = TypeHelper.replace(
+				sourceValues,
+				persister.getValues( copy ),
+				propertyTypes,
+				session,
+				copy,
+				copyCache,
+				ForeignKeyDirection.FROM_PARENT
+		);
+		persister.setValues( copy, copiedValues );
 
 		saveTransientEntity( copy, entityName, event.getRequestedId(), session, copyCache );
 
 		// cascade first, so that all unsaved objects get their
 		// copy created before we actually copy
 		super.cascadeAfterSave( session, persister, entity, copyCache );
 
-
-		copyValues( persister, entity, copy, session, copyCache, ForeignKeyDirection.TO_PARENT );
+		// this is the second pass through on a merge op, so here we limit the
+		// replacement to association types (value types were already replaced
+		// during the first pass)
+//		final Object[] newSourceValues = persister.getValues( entity );
+		final Object[] targetValues = TypeHelper.replaceAssociations(
+				sourceValues, // newSourceValues,
+				persister.getValues( copy ),
+				propertyTypes,
+				session,
+				copy,
+				copyCache,
+				ForeignKeyDirection.TO_PARENT
+		);
+		persister.setValues( copy, targetValues );
+		interceptor.postMerge( entity, copy, id, targetValues, null, propertyNames, propertyTypes );
 
 		// saveTransientEntity has been called using a copy that contains empty collections
-		// (copyValues uses `ForeignKeyDirection.FROM_PARENT`) then the PC may contain a wrong
+		// (copyValues uses ForeignKeyDirection.FROM_PARENT) then the PC may contain a wrong
 		// collection snapshot, the CollectionVisitor realigns the collection snapshot values
 		// with the final copy
 		new CollectionVisitor( copy, id, session )
@@ -315,9 +343,9 @@ protected void entityIsTransient(MergeEvent event, Object id, MergeContext copyC
 		event.setResult( copy );
 
 		if ( isPersistentAttributeInterceptable( copy ) ) {
-			final PersistentAttributeInterceptor interceptor =
+			final PersistentAttributeInterceptor attributeInterceptor =
 					asPersistentAttributeInterceptable( copy ).$$_hibernate_getInterceptor();
-			if ( interceptor == null ) {
+			if ( attributeInterceptor == null ) {
 				persister.getBytecodeEnhancementMetadata().injectInterceptor( copy, id, session );
 			}
 		}
@@ -383,29 +411,29 @@ protected void entityIsDetached(MergeEvent event, Object copiedId, Object origin
 		LOG.trace( "Merging detached instance" );
 
 		final Object entity = event.getEntity();
-		final EventSource source = event.getSession();
-		final EntityPersister persister = source.getEntityPersister( event.getEntityName(), entity );
+		final EventSource session = event.getSession();
+		final EntityPersister persister = session.getEntityPersister( event.getEntityName(), entity );
 		final String entityName = persister.getEntityName();
 		if ( originalId == null ) {
-			originalId = persister.getIdentifier( entity, source );
+			originalId = persister.getIdentifier( entity, session );
 		}
 		final Object clonedIdentifier = copiedId == null
 				? persister.getIdentifierType().deepCopy( originalId, event.getFactory() )
 				: copiedId;
 		final Object id = getDetachedEntityId( event, originalId, persister );
 		// we must clone embedded composite identifiers, or we will get back the same instance that we pass in
 		// apply the special MERGE fetch profile and perform the resolution (Session#get)
-		final Object result = source.getLoadQueryInfluencers().fromInternalFetchProfile(
+		final Object result = session.getLoadQueryInfluencers().fromInternalFetchProfile(
 				CascadingFetchProfile.MERGE,
-				() -> source.get( entityName, clonedIdentifier )
+				() -> session.get( entityName, clonedIdentifier )
 		);
 
 		if ( result == null ) {
 			LOG.trace( "Detached instance not found in database" );
 			// we got here because we assumed that an instance
 			// with an assigned id and no version was detached,
 			// when it was really transient (or deleted)
-			final Boolean knownTransient = persister.isTransient( entity, source );
+			final Boolean knownTransient = persister.isTransient( entity, session );
 			if ( knownTransient == Boolean.FALSE ) {
 				// we know for sure it's detached (generated id
 				// or a version property), and so the instance
@@ -425,8 +453,25 @@ protected void entityIsDetached(MergeEvent event, Object copiedId, Object origin
 			final Object target = targetEntity( event, entity, persister, id, result );
 			// cascade first, so that all unsaved objects get their
 			// copy created before we actually copy
-			cascadeOnMerge( source, persister, entity, copyCache );
-			copyValues( persister, entity, target, source, copyCache );
+			cascadeOnMerge( session, persister, entity, copyCache );
+
+			final Interceptor interceptor = session.getInterceptor();
+			final String[] propertyNames = persister.getPropertyNames();
+			final Type[] propertyTypes = persister.getPropertyTypes();
+
+			final Object[] sourceValues = persister.getValues( entity );
+			final Object[] originalValues = persister.getValues( target );
+			interceptor.preMerge( entity, sourceValues, propertyNames, propertyTypes );
+			final Object[] targetValues = TypeHelper.replace(
+					sourceValues,
+					originalValues,
+					propertyTypes,
+					session,
+					target,
+					copyCache
+			);
+			persister.setValues( target, targetValues );
+			interceptor.postMerge( entity, target, id, targetValues, originalValues, propertyNames, propertyTypes );
 			//copyValues works by reflection, so explicitly mark the entity instance dirty
 			markInterceptorDirty( entity, target );
 			event.setResult( result );
@@ -571,64 +616,6 @@ private static boolean existsInDatabase(Object entity, EventSource source, Entit
 		return entry != null && entry.isExistsInDatabase();
 	}
 
-	protected void copyValues(
-			final EntityPersister persister,
-			final Object entity,
-			final Object target,
-			final SessionImplementor source,
-			final MergeContext copyCache) {
-		if ( entity == target ) {
-			TypeHelper.replace( persister, entity, source, entity, copyCache );
-		}
-		else {
-			final Object[] copiedValues = TypeHelper.replace(
-					persister.getValues( entity ),
-					persister.getValues( target ),
-					persister.getPropertyTypes(),
-					source,
-					target,
-					copyCache
-			);
-			persister.setValues( target, copiedValues );
-		}
-	}
-
-	protected void copyValues(
-			final EntityPersister persister,
-			final Object entity,
-			final Object target,
-			final SessionImplementor source,
-			final MergeContext copyCache,
-			final ForeignKeyDirection foreignKeyDirection) {
-		final Object[] copiedValues;
-		if ( foreignKeyDirection == ForeignKeyDirection.TO_PARENT ) {
-			// this is the second pass through on a merge op, so here we limit the
-			// replacement to associations types (value types were already replaced
-			// during the first pass)
-			copiedValues = TypeHelper.replaceAssociations(
-					persister.getValues( entity ),
-					persister.getValues( target ),
-					persister.getPropertyTypes(),
-					source,
-					target,
-					copyCache,
-					foreignKeyDirection
-			);
-		}
-		else {
-			copiedValues = TypeHelper.replace(
-					persister.getValues( entity ),
-					persister.getValues( target ),
-					persister.getPropertyTypes(),
-					source,
-					target,
-					copyCache,
-					foreignKeyDirection
-			);
-		}
-		persister.setValues( target, copiedValues );
-	}
-
 	/**
 	 * Perform any cascades needed as part of this copy event.
 	 *

hibernate-core/src/main/java/org/hibernate/event/internal/EntityCopyNotAllowedObserver.java

@@ -45,12 +45,9 @@ public void entityCopyDetected(
 	}
 
 	private String getManagedOrDetachedEntityString(Object managedEntity, Object entity ) {
-		if ( entity == managedEntity) {
-			return  "Managed: [" + entity + "]";
-		}
-		else {
-			return "Detached: [" + entity + "]";
-		}
+		return entity == managedEntity
+				? "Managed: [" + entity + "]"
+				: "Detached: [" + entity + "]";
 	}
 
 	public void clear() {