HHH-17408 Test persisting and loading for a bidirectional OneToOne involving polymorphism

hibernate-core/src/test/java/org/hibernate/orm/test/onetoone/polymorphism/BidirectionalOneToOnePolymorphismTest.java

@@ -0,0 +1,169 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.orm.test.onetoone.polymorphism;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.hibernate.Hibernate;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+import jakarta.persistence.OneToOne;
+import org.assertj.core.api.InstanceOfAssertFactories;
+
+@DomainModel(annotatedClasses = {
+		BidirectionalOneToOnePolymorphismTest.Level1.class,
+		BidirectionalOneToOnePolymorphismTest.Level2.class,
+		BidirectionalOneToOnePolymorphismTest.DerivedLevel2.class,
+		BidirectionalOneToOnePolymorphismTest.Level3.class
+})
+@SessionFactory
+public class BidirectionalOneToOnePolymorphismTest {
+
+	@Test
+	public void persistAndLoad(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			Level1 level1 = new Level1();
+			level1.setId( 1 );
+
+			DerivedLevel2 level2 = new DerivedLevel2();
+			level2.setId( 2 );
+			level1.setDerivedLevel2( level2 );
+			level2.setLevel1( level1 );
+
+			Level3 level3 = new Level3();
+			level3.setId( 3 );
+			level2.setLevel3( level3 );
+			level3.setLevel2( level2 );
+
+			session.persist( level1 );
+			session.persist( level2 );
+			session.persist( level3 );
+		} );
+
+		// This succeeds, so the information was properly saved
+		scope.inTransaction( session -> assertThat( session.getReference( Level1.class, 1 ) )
+				.extracting( Level1::getDerivedLevel2 )
+				.isNotNull() );
+
+		// This succeeds too, so unproxying works at least in some cases
+		scope.inTransaction( session -> assertThat( session.getReference( Level2.class, 2 ) )
+				.extracting( Hibernate::unproxy, InstanceOfAssertFactories.type( DerivedLevel2.class ) )
+				.extracting( DerivedLevel2::getLevel1 )
+				.extracting( Level1::getDerivedLevel2 )
+				.isNotNull() );
+
+		// This fails for some reason
+		scope.inTransaction( session -> assertThat( session.getReference( Level3.class, 3 ) )
+				.extracting( Level3::getLevel2 )
+				.extracting( Hibernate::unproxy, InstanceOfAssertFactories.type( DerivedLevel2.class ) )
+				.extracting( DerivedLevel2::getLevel1 )
+				.extracting( Level1::getDerivedLevel2 )
+				.isNotNull() );
+	}
+
+	@Entity(name = "Level1")
+	static class Level1 {
+		@Id
+		private Integer id;
+
+		@OneToOne(mappedBy = "level1")
+		private DerivedLevel2 derivedLevel2;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public DerivedLevel2 getDerivedLevel2() {
+			return derivedLevel2;
+		}
+
+		public void setDerivedLevel2(DerivedLevel2 derivedLevel2) {
+			this.derivedLevel2 = derivedLevel2;
+		}
+	}
+
+	@Entity(name = "Level2")
+	static class Level2 {
+
+		@Id
+		private Integer id;
+
+		@OneToOne(mappedBy = "level2")
+		private Level3 level3;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public Level3 getLevel3() {
+			return level3;
+		}
+
+		public void setLevel3(Level3 level3) {
+			this.level3 = level3;
+		}
+
+	}
+
+	@Entity(name = "DerivedLevel2")
+	static class DerivedLevel2 extends Level2 {
+
+		@OneToOne
+		private Level1 level1;
+
+		public Level1 getLevel1() {
+			return level1;
+		}
+
+		public void setLevel1(Level1 level1) {
+			this.level1 = level1;
+		}
+
+	}
+
+	@Entity(name = "Level3")
+	static class Level3 {
+
+		@Id
+		private Integer id;
+
+		@OneToOne(fetch = FetchType.LAZY)
+		private Level2 level2;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public Level2 getLevel2() {
+			return level2;
+		}
+
+		public void setLevel2(Level2 level2) {
+			this.level2 = level2;
+		}
+
+	}
+}