HHH-18936 test for cascade REMOVE with @OnDelete(CASCADE)

hibernate-core/src/main/java/org/hibernate/action/internal/EntityDeleteAction.java

@@ -23,6 +23,7 @@
 import org.hibernate.event.spi.PreDeleteEventListener;
 import org.hibernate.metamodel.mapping.NaturalIdMapping;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.stat.internal.StatsHelper;
 import org.hibernate.stat.spi.StatisticsImplementor;
 
 /**
@@ -297,6 +298,14 @@ protected void removeCacheItem(Object ck) {
 		final EntityPersister persister = getPersister();
 		if ( persister.canWriteToCache() ) {
 			persister.getCacheAccessStrategy().remove( getSession(), ck );
+
+			final StatisticsImplementor statistics = getSession().getFactory().getStatistics();
+			if ( statistics.isStatisticsEnabled() ) {
+				statistics.entityCacheRemove(
+						StatsHelper.getRootEntityRole( persister ),
+						getPersister().getCacheAccessStrategy().getRegion().getName()
+				);
+			}
 		}
 	}
 }

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

@@ -15,10 +15,33 @@
 /**
  * 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/stat/CacheRegionStatistics.java

@@ -39,6 +39,11 @@ public interface CacheRegionStatistics extends Serializable {
 	 */
 	long getMissCount();
 
+	/**
+	 * The number of removals since the last Statistics clearing
+	 */
+	long getRemoveCount();
+
 	/**
 	 * The number of elements currently in memory within the cache provider.
 	 * <p>

hibernate-core/src/main/java/org/hibernate/stat/CacheableDataStatistics.java

@@ -36,4 +36,10 @@ public interface CacheableDataStatistics extends Serializable {
 	 * configured cache region since the last Statistics clearing
 	 */
 	long getCacheMissCount();
+
+	/**
+	 * The number of evictions from the configured cache region since
+	 * the last Statistics clearing
+	 */
+	long getCacheRemoveCount();
 }

hibernate-core/src/main/java/org/hibernate/stat/internal/AbstractCacheableDataStatistics.java

@@ -21,6 +21,7 @@ public abstract class AbstractCacheableDataStatistics implements CacheableDataSt
 	private final @Nullable LongAdder cacheHitCount;
 	private final @Nullable LongAdder cacheMissCount;
 	private final @Nullable LongAdder cachePutCount;
+	private final @Nullable LongAdder cacheRemoveCount;
 
 	public AbstractCacheableDataStatistics(Supplier<@Nullable Region> regionSupplier) {
 		final Region region = regionSupplier.get();
@@ -29,12 +30,14 @@ public AbstractCacheableDataStatistics(Supplier<@Nullable Region> regionSupplier
 			this.cacheHitCount = null;
 			this.cacheMissCount = null;
 			this.cachePutCount = null;
+			this.cacheRemoveCount = null;
 		}
 		else {
 			this.cacheRegionName = region.getName();
 			this.cacheHitCount = new LongAdder();
 			this.cacheMissCount = new LongAdder();
 			this.cachePutCount = new LongAdder();
+			this.cacheRemoveCount = new LongAdder();
 		}
 	}
 
@@ -43,6 +46,7 @@ public AbstractCacheableDataStatistics(Supplier<@Nullable Region> regionSupplier
 		return cacheRegionName;
 	}
 
+	@Override
 	public long getCacheHitCount() {
 		if ( cacheRegionName == null ) {
 			return NOT_CACHED_COUNT;
@@ -51,6 +55,7 @@ public long getCacheHitCount() {
 		return NullnessUtil.castNonNull( cacheHitCount ).sum();
 	}
 
+	@Override
 	public long getCachePutCount() {
 		if ( cacheRegionName == null ) {
 			return NOT_CACHED_COUNT;
@@ -59,6 +64,7 @@ public long getCachePutCount() {
 		return NullnessUtil.castNonNull( cachePutCount ).sum();
 	}
 
+	@Override
 	public long getCacheMissCount() {
 		if ( cacheRegionName == null ) {
 			return NOT_CACHED_COUNT;
@@ -67,6 +73,15 @@ public long getCacheMissCount() {
 		return NullnessUtil.castNonNull( cacheMissCount ).sum();
 	}
 
+	@Override
+	public long getCacheRemoveCount() {
+		if ( cacheRegionName == null ) {
+			return NOT_CACHED_COUNT;
+		}
+
+		return NullnessUtil.castNonNull( cacheRemoveCount ).sum();
+	}
+
 	public void incrementCacheHitCount() {
 		if ( cacheRegionName == null ) {
 			throw new IllegalStateException( "Illegal attempt to increment cache hit count for non-cached data" );
@@ -91,6 +106,14 @@ public void incrementCachePutCount() {
 		NullnessUtil.castNonNull( cachePutCount ).increment();
 	}
 
+	public void incrementCacheRemoveCount() {
+		if ( cacheRegionName == null ) {
+			throw new IllegalStateException( "Illegal attempt to increment cache put count for non-cached data" );
+		}
+
+		NullnessUtil.castNonNull( cacheRemoveCount ).increment();
+	}
+
 	protected void appendCacheStats(StringBuilder buf) {
 		buf.append( ",cacheRegion=" ).append( cacheRegionName );
 
@@ -100,7 +123,8 @@ protected void appendCacheStats(StringBuilder buf) {
 
 		buf.append( ",cacheHitCount=" ).append( getCacheHitCount() )
 				.append( ",cacheMissCount=" ).append( getCacheMissCount() )
-				.append( ",cachePutCount=" ).append( getCachePutCount() );
+				.append( ",cachePutCount=" ).append( getCachePutCount() )
+				.append( ",cacheRemoveCount=" ).append( getCacheRemoveCount() );
 
 	}
 }

hibernate-core/src/main/java/org/hibernate/stat/internal/CacheRegionStatisticsImpl.java

@@ -22,6 +22,7 @@ public class CacheRegionStatisticsImpl implements CacheRegionStatistics, Seriali
 	private final LongAdder hitCount = new LongAdder();
 	private final LongAdder missCount = new LongAdder();
 	private final LongAdder putCount = new LongAdder();
+	private final LongAdder removeCount = new LongAdder();
 
 	CacheRegionStatisticsImpl(Region region) {
 		this.region = region;
@@ -47,6 +48,11 @@ public long getPutCount() {
 		return putCount.sum();
 	}
 
+	@Override
+	public long getRemoveCount() {
+		return removeCount.sum();
+	}
+
 	@Override
 	public long getElementCountInMemory() {
 		return region instanceof ExtendedStatisticsSupport extended
@@ -80,13 +86,19 @@ void incrementPutCount() {
 		putCount.increment();
 	}
 
+
+	public void incrementRemoveCount() {
+		removeCount.increment();
+	}
+
 	@Override
 	public String toString() {
 		String buf = "CacheRegionStatistics" +
 				"[region=" + region.getName() +
 				",hitCount=" + this.hitCount +
 				",missCount=" + this.missCount +
 				",putCount=" + this.putCount +
+				",removeCount=" + this.removeCount +
 				",elementCountInMemory=" + this.getElementCountInMemory() +
 				",elementCountOnDisk=" + this.getElementCountOnDisk() +
 				",sizeInMemory=" + this.getSizeInMemory() +

hibernate-core/src/main/java/org/hibernate/stat/internal/StatisticsImpl.java

@@ -355,6 +355,13 @@ public void entityCacheMiss(NavigableRole entityName, String regionName) {
 		getEntityStatistics( entityName.getFullPath() ).incrementCacheMissCount();
 	}
 
+	@Override
+	public void entityCacheRemove(NavigableRole entityName, String regionName) {
+		secondLevelCacheMissCount.increment();
+		getDomainDataRegionStatistics( regionName ).incrementRemoveCount();
+		getEntityStatistics( entityName.getFullPath() ).incrementCacheRemoveCount();
+	}
+
 
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 	// Collection stats

hibernate-core/src/main/java/org/hibernate/stat/spi/StatisticsImplementor.java

@@ -148,24 +148,31 @@ public interface StatisticsImplementor extends Statistics, Service {
 	/**
 	 * Callback indicating a put into second level cache.
 	 *
-	 * @apiNote `entityName` should be the root entity name
+	 * @apiNote {@code entityName} should be the root entity name
 	 */
 	void entityCachePut(NavigableRole entityName, String regionName);
 
 	/**
 	 * Callback indicating a get from second level cache resulted in a hit.
 	 *
-	 * @apiNote `entityName` should be the root entity name
+	 * @apiNote {@code entityName} should be the root entity name
 	 */
 	void entityCacheHit(NavigableRole entityName, String regionName);
 
 	/**
 	 * Callback indicating a get from second level cache resulted in a miss.
 	 *
-	 * @apiNote `entityName` should be the root entity name
+	 * @apiNote {@code entityName} should be the root entity name
 	 */
 	void entityCacheMiss(NavigableRole entityName, String regionName);
 
+	/**
+	 * Callback indicating a removal from second level cache.
+	 *
+	 * @apiNote {@code entityName} should be the root entity name
+	 */
+	void entityCacheRemove(NavigableRole rootEntityRole, String name);
+
 	/**
 	 * Callback indicating a put into second level cache.
 	 *

hibernate-core/src/test/java/org/hibernate/orm/test/ondeletecascade/OnDeleteCascadeRemoveTest.java

@@ -0,0 +1,122 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.ondeletecascade;
+
+import jakarta.persistence.Cacheable;
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.OneToMany;
+import org.hibernate.Hibernate;
+import org.hibernate.SessionFactory;
+import org.hibernate.annotations.OnDelete;
+import org.hibernate.annotations.OnDeleteAction;
+import org.hibernate.annotations.SQLDelete;
+import org.hibernate.engine.spi.SessionImplementor;
+import org.hibernate.stat.EntityStatistics;
+import org.hibernate.stat.Statistics;
+import org.hibernate.testing.orm.junit.EntityManagerFactoryScope;
+import org.hibernate.testing.orm.junit.Jpa;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@Jpa(annotatedClasses =
+		{OnDeleteCascadeRemoveTest.Parent.class,
+		OnDeleteCascadeRemoveTest.Child.class},
+		generateStatistics = true,
+		useCollectingStatementInspector = true)
+class OnDeleteCascadeRemoveTest {
+	@Test
+	void testOnDeleteCascadeRemove1(EntityManagerFactoryScope scope) {
+		Statistics statistics =
+				scope.getEntityManagerFactory().unwrap( SessionFactory.class )
+						.getStatistics();
+		statistics.clear();
+		scope.getCollectingStatementInspector().clear();
+		scope.inTransaction( em -> {
+			Parent parent = new Parent();
+			Child child = new Child();
+			parent.children.add( child );
+			child.parent = parent;
+			em.persist( parent );
+		} );
+		scope.inTransaction( em -> {
+			Parent parent = em.find( Parent.class, 0L );
+			assertFalse( Hibernate.isInitialized( parent.children ) );
+			em.remove( parent );
+			// note: ideally we would skip the initialization here
+			assertTrue( Hibernate.isInitialized( parent.children ) );
+		});
+		EntityStatistics entityStatistics = statistics.getEntityStatistics( Child.class.getName() );
+		assertEquals( 1L, entityStatistics.getDeleteCount() );
+		assertEquals( 1L, entityStatistics.getCacheRemoveCount() );
+		assertEquals( 5, scope.getCollectingStatementInspector().getSqlQueries().size() );
+		long children =
+				scope.fromTransaction( em -> em.createQuery( "select count(*) from CascadeChild", Long.class )
+						.getSingleResult() );
+		assertEquals( 0L, children );
+	}
+
+	@Test
+	void testOnDeleteCascadeRemove2(EntityManagerFactoryScope scope) {
+		Statistics statistics =
+				scope.getEntityManagerFactory().unwrap( SessionFactory.class )
+						.getStatistics();
+		statistics.clear();
+		scope.getCollectingStatementInspector().clear();
+		scope.inTransaction( em -> {
+			Parent parent = new Parent();
+			Child child = new Child();
+			parent.children.add( child );
+			child.parent = parent;
+			em.persist( parent );
+		} );
+		scope.inTransaction( em -> {
+			Parent parent = em.find( Parent.class, 0L );
+			assertEquals(1, parent.children.size());
+			assertTrue( Hibernate.isInitialized( parent.children ) );
+			em.remove( parent );
+			assertTrue( em.unwrap( SessionImplementor.class )
+					.getPersistenceContext()
+					.getEntry( parent.children.iterator().next() )
+					.getStatus().isDeletedOrGone() );
+		});
+		EntityStatistics entityStatistics = statistics.getEntityStatistics( Child.class.getName() );
+		assertEquals( 1L, entityStatistics.getDeleteCount() );
+		assertEquals( 1L, entityStatistics.getCacheRemoveCount() );
+		assertEquals( 5, scope.getCollectingStatementInspector().getSqlQueries().size() );
+		long children =
+				scope.fromTransaction( em -> em.createQuery( "select count(*) from CascadeChild", Long.class )
+						.getSingleResult() );
+		assertEquals( 0L, children );
+	}
+
+	@Entity(name="CascadeParent")
+	static class Parent {
+		@Id
+		long id;
+		@OneToMany(mappedBy = "parent",
+				cascade = {CascadeType.PERSIST, CascadeType.REMOVE})
+		@OnDelete(action = OnDeleteAction.CASCADE)
+		Set<Child> children = new HashSet<>();
+	}
+	@Entity(name="CascadeChild")
+	@Cacheable
+	@SQLDelete( sql = "should never happen" )
+	static class Child {
+		@Id
+		long id;
+		@OnDelete(action = OnDeleteAction.CASCADE)
+		@ManyToOne
+		Parent parent;
+	}
+}

hibernate-core/src/test/java/org/hibernate/orm/test/OnDeleteTest.java → hibernate-core/src/test/java/org/hibernate/orm/test/ondeletecascade/OnDeleteTest.java

@@ -2,7 +2,7 @@
  * SPDX-License-Identifier: Apache-2.0
  * Copyright Red Hat Inc. and Hibernate Authors
  */
-package org.hibernate.orm.test;
+package org.hibernate.orm.test.ondeletecascade;
 
 import jakarta.persistence.Entity;
 import jakarta.persistence.Id;

hibernate-core/src/test/java/org/hibernate/orm/test/OnDeleteTest2.java → hibernate-core/src/test/java/org/hibernate/orm/test/ondeletecascade/OnDeleteTest2.java

@@ -2,7 +2,7 @@
  * SPDX-License-Identifier: Apache-2.0
  * Copyright Red Hat Inc. and Hibernate Authors
  */
-package org.hibernate.orm.test;
+package org.hibernate.orm.test.ondeletecascade;
 
 import jakarta.persistence.Entity;
 import jakarta.persistence.Id;