HHH-18936 remove parent with @OnDelete(CASCADE) leads to TransientObjectException

hibernate-core/src/main/java/org/hibernate/annotations/OnDelete.java

@@ -17,10 +17,33 @@
 /**
  * Specifies an {@code on delete} action for a foreign key constraint.
  * The most common usage is {@code @OnDelete(action = CASCADE)}.
+ * <pre>
+ * &#064;ManyToOne
+ * &#064;OnDelete(action = CASCADE)
+ * Parent parent;
+ * </pre>
  * Note that this results in an {@code on delete cascade} clause in
  * the DDL definition of the foreign key. It's completely different
  * to {@link jakarta.persistence.CascadeType#REMOVE}.
  * <p>
+ * In fact, {@code @OnDelete} may be combined with {@code cascade=REMOVE}.
+ * <pre>
+ * &#064;ManyToOne(cascade = REMOVE)
+ * &#064;OnDelete(action = CASCADE)
+ * Parent parent;
+ * </pre>
+ * <ul>
+ * <li>If {@code @OnDelete(action = CASCADE)} is used in conjunction
+ *     with {@code cascade=REMOVE}, then associated entities are fetched
+ *     from the database, marked deleted in the persistence context,
+ *     and evicted from the second-level cache.
+ * <li>If {@code @OnDelete(action = CASCADE)} is used on its own,
+ *     <em>without</em> {@code cascade=REMOVE}, then associated
+ *     entities are not fetched from the database, are not marked
+ *     deleted in the persistence context, and are not automatically
+ *     evicted from the second-level cache.
+ * </ul>
+ * <p>
  * Like database triggers, {@code on delete} actions can cause state
  * held in memory to lose synchronization with the database.
  *

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

@@ -14,6 +14,7 @@
 
 import org.hibernate.HibernateException;
 import org.hibernate.bytecode.enhance.spi.interceptor.LazyAttributeLoadingInterceptor;
+import org.hibernate.annotations.OnDeleteAction;
 import org.hibernate.collection.spi.PersistentCollection;
 import org.hibernate.engine.spi.CascadeStyle;
 import org.hibernate.engine.spi.CascadingAction;
@@ -137,6 +138,7 @@ public static <T> void cascade(
 				final boolean isUninitializedProperty =
 						hasUninitializedLazyProperties &&
 						!persister.getBytecodeEnhancementMetadata().isAttributeLoaded( parent, propertyName );
+				final boolean isCascadeDeleteEnabled = cascadeDeleteEnabled( action, persister, i );
 
 				if ( style.doCascade( action ) ) {
 					final Object child;
@@ -200,7 +202,7 @@ else if ( action.performOnLazyProperty() && type instanceof EntityType ) {
 							style,
 							propertyName,
 							anything,
-							false
+							isCascadeDeleteEnabled
 					);
 				}
 				else {
@@ -215,7 +217,7 @@ else if ( action.performOnLazyProperty() && type instanceof EntityType ) {
 								type,
 								style,
 								propertyName,
-								false
+								isCascadeDeleteEnabled
 						);
 					}
 				}
@@ -471,8 +473,8 @@ private static <T> void cascadeComponent(
 						componentPropertyStyle,
 						subPropertyName,
 						anything,
-						false
-					);
+						cascadeDeleteEnabled( action, componentType, i )
+				);
 			}
 		}
 	}
@@ -542,7 +544,7 @@ private static <T> void cascadeCollection(
 				style,
 				elemType,
 				anything,
-				persister.isCascadeDeleteEnabled()
+				cascadeDeleteEnabled( action, persister )
 			);
 		}
 	}
@@ -678,4 +680,19 @@ private static void deleteOrphans(EventSource eventSource, String entityName, Pe
 			}
 		}
 	}
+
+	private static <T> boolean cascadeDeleteEnabled(CascadingAction<T> action, CollectionPersister persister) {
+		return action.directionAffectedByCascadeDelete() == ForeignKeyDirection.FROM_PARENT
+			&& persister.isCascadeDeleteEnabled();
+	}
+
+	private static <T> boolean cascadeDeleteEnabled(CascadingAction<T> action, EntityPersister persister, int i) {
+		return action.directionAffectedByCascadeDelete() == ForeignKeyDirection.TO_PARENT
+			&& persister.getEntityMetamodel().getPropertyOnDeleteActions()[i] == OnDeleteAction.CASCADE;
+	}
+
+	private static <T> boolean cascadeDeleteEnabled(CascadingAction<T> action, CompositeType componentType, int i) {
+		return action.directionAffectedByCascadeDelete() == ForeignKeyDirection.TO_PARENT
+			&& componentType.getOnDeleteAction( i ) == OnDeleteAction.CASCADE;
+	}
 }

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

@@ -7,16 +7,22 @@
 package org.hibernate.engine.spi;
 
 import java.util.Iterator;
+import java.util.List;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.hibernate.HibernateException;
+import org.hibernate.Incubating;
 import org.hibernate.event.spi.EventSource;
 import org.hibernate.persister.entity.EntityPersister;
 import org.hibernate.type.CollectionType;
+import org.hibernate.type.ForeignKeyDirection;
 import org.hibernate.type.Type;
 
 /**
  * A session action that may be cascaded from parent entity to its children
  *
+ * @param <T> The type of some context propagated with the cascading action
+ *
  * @author Gavin King
  * @author Steve Ebersole
  */
@@ -27,10 +33,9 @@ public interface CascadingAction<T> {
 	 *
 	 * @param session The session within which the cascade is occurring.
 	 * @param child The child to which cascading should be performed.
-	 * @param entityName The child's entity name
-	 * @param anything Anything ;)  Typically some form of cascade-local cache
-	 * which is specific to each CascadingAction type
-	 * @param isCascadeDeleteEnabled Are cascading deletes enabled.
+	 * @param anything Some context specific to the kind of {@link CascadingAction}
+	 * @param isCascadeDeleteEnabled Whether the foreign key is declared with
+	 *        {@link org.hibernate.annotations.OnDeleteAction#CASCADE on delete cascade}.
 	 */
 	void cascade(
 			EventSource session,
@@ -92,4 +97,18 @@ default void noCascade(EventSource session, Object parent, EntityPersister persi
 	 * Should this action be performed (or noCascade consulted) in the case of lazy properties.
 	 */
 	boolean performOnLazyProperty();
+
+	/**
+	 * The cascade direction in which we care whether the foreign key is declared with
+	 * {@link org.hibernate.annotations.OnDeleteAction#CASCADE on delete cascade}.
+	 *
+	 * @apiNote This allows us to reuse the long-existing boolean parameter of
+	 *          {@link #cascade(EventSource, Object, String, Object, boolean)}
+	 *          for multiple purposes.
+	 *
+	 */
+	@Incubating @Nullable
+	default ForeignKeyDirection directionAffectedByCascadeDelete(){
+		return null;
+	}
 }

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

@@ -6,6 +6,7 @@
  */
 package org.hibernate.engine.spi;
 
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.hibernate.HibernateException;
 import org.hibernate.Internal;
 import org.hibernate.LockMode;
@@ -20,6 +21,7 @@
 import org.hibernate.event.spi.RefreshContext;
 import org.hibernate.internal.CoreMessageLogger;
 import org.hibernate.type.CollectionType;
+import org.hibernate.type.ForeignKeyDirection;
 import org.jboss.logging.Logger;
 
 import java.util.Iterator;
@@ -73,6 +75,11 @@ public boolean deleteOrphans() {
 			return true;
 		}
 
+		@Override
+		public ForeignKeyDirection directionAffectedByCascadeDelete() {
+			return ForeignKeyDirection.FROM_PARENT;
+		}
+
 		@Override
 		public String toString() {
 			return "ACTION_DELETE";
@@ -378,7 +385,7 @@ public void cascade(
 				Void context,
 				boolean isCascadeDeleteEnabled)
 				throws HibernateException {
-			if ( child != null && isChildTransient( session, child, entityName ) ) {
+			if ( child != null && isChildTransient( session, child, entityName, isCascadeDeleteEnabled ) ) {
 				throw new TransientObjectException( "persistent instance references an unsaved transient instance of '"
 						+ entityName + "' (save the transient instance before flushing)" );
 				//TODO: should be TransientPropertyValueException
@@ -419,13 +426,18 @@ public boolean performOnLazyProperty() {
 			return false;
 		}
 
+		@Override
+		public ForeignKeyDirection directionAffectedByCascadeDelete() {
+			return ForeignKeyDirection.TO_PARENT;
+		}
+
 		@Override
 		public String toString() {
 			return "ACTION_CHECK_ON_FLUSH";
 		}
 	};
 
-	private static boolean isChildTransient(EventSource session, Object child, String entityName) {
+	private static boolean isChildTransient(EventSource session, Object child, String entityName, boolean isCascadeDeleteEnabled) {
 		if ( isHibernateProxy( child ) ) {
 			// a proxy is always non-transient
 			// and ForeignKeys.isTransient()
@@ -440,7 +452,11 @@ private static boolean isChildTransient(EventSource session, Object child, Strin
 				// we are good, even if it's not yet
 				// inserted, since ordering problems
 				// are detected and handled elsewhere
-				return entry.getStatus().isDeletedOrGone();
+				return entry.getStatus().isDeletedOrGone()
+					// if the foreign key is 'on delete cascade'
+					// we don't have to throw because the database
+					// will delete the parent for us
+					&& !isCascadeDeleteEnabled;
 			}
 			else {
 				// TODO: check if it is a merged entity which has not yet been flushed
@@ -495,6 +511,11 @@ public abstract static class BaseCascadingAction<T> implements CascadingAction<T
 		public boolean performOnLazyProperty() {
 			return true;
 		}
+
+		@Override @Nullable
+		public ForeignKeyDirection directionAffectedByCascadeDelete() {
+			return null;
+		}
 	}
 
 	/**

hibernate-core/src/main/java/org/hibernate/mapping/Property.java

@@ -14,6 +14,7 @@
 import org.hibernate.HibernateException;
 import org.hibernate.Internal;
 import org.hibernate.MappingException;
+import org.hibernate.annotations.OnDeleteAction;
 import org.hibernate.boot.model.relational.Database;
 import org.hibernate.bytecode.enhance.spi.interceptor.EnhancementHelper;
 import org.hibernate.cfg.AvailableSettings;
@@ -86,7 +87,7 @@ public boolean isSynthetic() {
 	public Type getType() throws MappingException {
 		return value.getType();
 	}
-	
+
 	public int getColumnSpan() {
 		return value.getColumnSpan();
 	}
@@ -106,11 +107,11 @@ public java.util.List<Selectable> getSelectables() {
 	public java.util.List<Column> getColumns() {
 		return value.getColumns();
 	}
-	
+
 	public String getName() {
 		return name;
 	}
-	
+
 	public boolean isComposite() {
 		return value instanceof Component;
 	}
@@ -137,6 +138,10 @@ public void resetOptional(boolean optional) {
 		}
 	}
 
+	public OnDeleteAction getOnDeleteAction() {
+		return value instanceof ToOne ? ( (ToOne) value ).getOnDeleteAction() : null;
+	}
+
 	/**
 	 * @deprecated this method is no longer used
 	 */
@@ -158,7 +163,7 @@ else if ( type instanceof CollectionType ) {
 			return getCollectionCascadeStyle( collection.getElement().getType(), cascade );
 		}
 		else {
-			return getCascadeStyle( cascade );			
+			return getCascadeStyle( cascade );
 		}
 	}
 
@@ -192,7 +197,7 @@ else if ( elementType instanceof ComponentType ) {
 			return getCascadeStyle( cascade );
 		}
 	}
-	
+
 	private static CascadeStyle getCascadeStyle(String cascade) {
 		if ( cascade==null || cascade.equals("none") ) {
 			return CascadeStyles.NONE;
@@ -205,9 +210,9 @@ private static CascadeStyle getCascadeStyle(String cascade) {
 				styles[i++] = CascadeStyles.getCascadeStyle( tokens.nextToken() );
 			}
 			return new CascadeStyles.MultipleCascadeStyle(styles);
-		}		
+		}
 	}
-	
+
 	public String getCascade() {
 		return cascade;
 	}
@@ -231,7 +236,7 @@ public boolean isUpdateable() {
 	}
 
 	public boolean isInsertable() {
-		// if the property mapping consists of all formulas, 
+		// if the property mapping consists of all formulas,
 		// make it non-insertable
 		return insertable && value.hasAnyInsertableColumns();
 	}
@@ -318,7 +323,7 @@ public boolean isValid(Mapping mapping) throws MappingException {
 	public String toString() {
 		return getClass().getSimpleName() + '(' + name + ')';
 	}
-	
+
 	public void setLazy(boolean lazy) {
 		this.lazy=lazy;
 	}
@@ -364,11 +369,11 @@ public boolean isOptimisticLocked() {
 	public void setOptimisticLocked(boolean optimisticLocked) {
 		this.optimisticLocked = optimisticLocked;
 	}
-	
+
 	public boolean isOptional() {
 		return optional;
 	}
-	
+
 	public void setOptional(boolean optional) {
 		this.optional = optional;
 	}
@@ -384,7 +389,7 @@ public void setPersistentClass(PersistentClass persistentClass) {
 	public boolean isSelectable() {
 		return selectable;
 	}
-	
+
 	public void setSelectable(boolean selectable) {
 		this.selectable = selectable;
 	}

hibernate-core/src/main/java/org/hibernate/tuple/AbstractNonIdentifierAttribute.java

@@ -7,6 +7,7 @@
 package org.hibernate.tuple;
 
 import org.hibernate.FetchMode;
+import org.hibernate.annotations.OnDeleteAction;
 import org.hibernate.engine.spi.CascadeStyle;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.persister.walking.spi.AttributeSource;
@@ -94,6 +95,11 @@ public CascadeStyle getCascadeStyle() {
 		return attributeInformation.getCascadeStyle();
 	}
 
+	@Override
+	public OnDeleteAction getOnDeleteAction() {
+		return attributeInformation.getOnDeleteAction();
+	}
+
 	@Override
 	public FetchMode getFetchMode() {
 		return attributeInformation.getFetchMode();