HHH-2862, HHH-1914 Make collection replacement a first class operation on PersistenceContext

Author: beikov

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

@@ -1075,6 +1075,23 @@ public void addNewCollection(CollectionPersister persister, PersistentCollection
 		addCollection( collection, persister );
 	}
 
+	@Override
+	public void replaceCollection(CollectionPersister persister, PersistentCollection<?> collection) {
+		assert !collection.isDirectlyAccessible();
+		final CollectionEntry entry = new CollectionEntry( collection, session.getFactory() );
+		final IdentityMap<PersistentCollection<?>, CollectionEntry> collectionEntries = getOrInitializeCollectionEntries();
+		collectionEntries.put( collection, entry );
+		final CollectionKey collectionKey = new CollectionKey( entry.getLoadedPersister(), collection.getKey() );
+		final PersistentCollection<?> old = addCollectionByKey( collectionKey, collection );
+		if ( old == null ) {
+			throw new HibernateException( "No collection for replacement found: " + collectionKey.getRole() );
+		}
+		if ( !old.isDirectlyAccessible() ) {
+			throw new HibernateException( "Replacement of not directly accessible collection found: " + collectionKey.getRole() );
+		}
+		collectionEntries.remove( old );
+	}
+
 	/**
 	 * Add a collection to the cache, with a given collection entry.
 	 *

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

@@ -25,6 +25,7 @@
 
 import org.checkerframework.checker.nullness.qual.Nullable;
 
+
 /**
  * Represents the state of "stuff" Hibernate is tracking, including (not exhaustive):
  * <ul>
@@ -408,6 +409,13 @@ void addInitializedDetachedCollection(
 			CollectionPersister collectionPersister,
 			PersistentCollection<?> collection);
 
+	/**
+	 * Replaces a directly accessible collection with the given one
+	 * @param collection The collection to be associated with the persistence context
+	 * @since 7.0
+	 */
+	void replaceCollection(CollectionPersister persister, PersistentCollection<?> collection);
+
 	/**
 	 * add a collection we just pulled out of the cache (does not need initializing)
 	 */

hibernate-core/src/main/java/org/hibernate/type/CollectionType.java

@@ -671,7 +671,7 @@ private Object replaceOriginal(
 				final PersistentCollection<?> persistentCollection = instantiate( session, collectionPersister, key );
 				persistentCollection.initializeEmptyCollection( collectionPersister );
 				persistentCollection.setSnapshot( key, existingPersistentCollection.getRole(), existingPersistentCollection.getStoredSnapshot() );
-				session.getPersistenceContextInternal().addInitializedDetachedCollection( collectionPersister, persistentCollection );
+				session.getPersistenceContextInternal().replaceCollection( collectionPersister, persistentCollection );
 				target = persistentCollection;
 			}
 			//TODO: this is a little inefficient, don't need to do a whole