HHH-16459 Expand existing test of generic associations to ToOne associations

hibernate-core/src/test/java/org/hibernate/orm/test/annotations/generics/GenericToManyAssociationTest.java

@@ -38,13 +38,13 @@
  */
 @SessionFactory
 @DomainModel( annotatedClasses = {
-		GenericAssociationTest.AbstractParent.class,
+		GenericToManyAssociationTest.AbstractParent.class,
-		GenericAssociationTest.Parent.class,
+		GenericToManyAssociationTest.Parent.class,
-		GenericAssociationTest.AbstractChild.class,
+		GenericToManyAssociationTest.AbstractChild.class,
-		GenericAssociationTest.Child.class
+		GenericToManyAssociationTest.Child.class
 } )
 @Jira( "https://hibernate.atlassian.net/browse/HHH-16378" )
-public class GenericAssociationTest {
+public class GenericToManyAssociationTest {
 	@BeforeAll
 	public void setUp(SessionFactoryScope scope) {
 		scope.inTransaction( session -> {

hibernate-core/src/test/java/org/hibernate/orm/test/annotations/generics/GenericToOneAssociationTest.java

@@ -0,0 +1,187 @@
+/*
+ * 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.annotations.generics;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.hibernate.query.criteria.JpaPath;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.Jira;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.MappedSuperclass;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.OneToOne;
+import jakarta.persistence.criteria.CriteriaBuilder;
+import jakarta.persistence.criteria.CriteriaQuery;
+import jakarta.persistence.criteria.Join;
+import jakarta.persistence.criteria.Path;
+import jakarta.persistence.criteria.Root;
+
+/**
+ * @author Yoann Rodière
+ * @author Marco Belladelli
+ */
+@SessionFactory
+@DomainModel( annotatedClasses = {
+		GenericToOneAssociationTest.AbstractParent.class,
+		GenericToOneAssociationTest.Parent.class,
+		GenericToOneAssociationTest.AbstractChild.class,
+		GenericToOneAssociationTest.Child.class
+} )
+@Jira( "https://hibernate.atlassian.net/browse/HHH-16378" )
+public class GenericToOneAssociationTest {
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Parent parent = new Parent( 1L );
+			session.persist( parent );
+			final Child child = new Child( 2L );
+			child.setParent( parent );
+			parent.setChild( child );
+			session.persist( child );
+		} );
+	}
+
+	@AfterAll
+	public void tearDown(SessionFactoryScope scope) {
+		scope.inTransaction( session -> session.createQuery( "from Parent", Parent.class )
+				.getResultList()
+				.forEach( p -> p.setChild( null ) ) );
+		scope.inTransaction( session -> {
+			session.createMutationQuery( "delete from Child" ).executeUpdate();
+			session.createMutationQuery( "delete from Parent" ).executeUpdate();
+		} );
+	}
+
+	@Test
+	public void testParentQuery(SessionFactoryScope scope) {
+		scope.inTransaction( session -> assertThat( session.createQuery(
+				"select parent.id from Child",
+				Long.class
+		).getSingleResult() ).isEqualTo( 1L ) );
+	}
+
+	@Test
+	public void testParentCriteriaQuery(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final CriteriaBuilder cb = session.getCriteriaBuilder();
+			final CriteriaQuery<Long> query = cb.createQuery( Long.class );
+			final Root<Child> root = query.from( Child.class );
+			final Path<Parent> parent = root.get( "parent" );
+			// generic attributes are always reported as Object java type
+			assertThat( parent.getJavaType() ).isEqualTo( Object.class );
+			assertThat( parent.getModel() ).isSameAs( root.getModel().getAttribute( "parent" ) );
+			assertThat( ( (JpaPath<?>) parent ).getResolvedModel().getBindableJavaType() ).isEqualTo( Parent.class );
+			final Long result = session.createQuery( query.select( parent.get( "id" ) ) ).getSingleResult();
+			assertThat( result ).isEqualTo( 1L );
+		} );
+	}
+
+	@Test
+	public void testChildQuery(SessionFactoryScope scope) {
+		scope.inTransaction( session -> assertThat( session.createQuery(
+				"select c.id from Parent p join p.child c",
+				Long.class
+		).getSingleResult() ).isEqualTo( 2L ) );
+	}
+
+	@Test
+	public void testChildCriteriaQuery(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final CriteriaBuilder cb = session.getCriteriaBuilder();
+			final CriteriaQuery<Long> query = cb.createQuery( Long.class );
+			final Root<Parent> root = query.from( Parent.class );
+			final Join<Parent, Child> join = root.join( "child" );
+			// generic attributes are always reported as Object java type
+			assertThat( join.getJavaType() ).isEqualTo( Object.class );
+			assertThat( join.getModel() ).isSameAs( root.getModel().getAttribute( "child" ) );
+			assertThat( ( (JpaPath<?>) join ).getResolvedModel().getBindableJavaType() ).isEqualTo( Child.class );
+			final Long result = session.createQuery( query.select( join.get( "id" ) ) ).getSingleResult();
+			assertThat( result ).isEqualTo( 2L );
+		} );
+	}
+
+	@MappedSuperclass
+	public abstract static class AbstractParent<T> {
+		@OneToOne
+		private T child;
+
+		public T getChild() {
+			return child;
+		}
+
+		public void setChild(T child) {
+			this.child = child;
+		}
+	}
+
+	@Entity( name = "Parent" )
+	public static class Parent extends AbstractParent<Child> {
+		@Id
+		private Long id;
+
+		public Parent() {
+		}
+
+		public Parent(Long id) {
+			this.id = id;
+		}
+
+		public Long getId() {
+			return this.id;
+		}
+	}
+
+	@MappedSuperclass
+	public abstract static class AbstractChild<T> {
+		@OneToOne(mappedBy = "child")
+		private T parent;
+
+		public AbstractChild() {
+		}
+
+		public abstract Long getId();
+
+		public T getParent() {
+			return this.parent;
+		}
+
+		public void setParent(T parent) {
+			this.parent = parent;
+		}
+	}
+
+	@Entity( name = "Child" )
+	public static class Child extends AbstractChild<Parent> {
+		@Id
+		protected Long id;
+
+		public Child() {
+		}
+
+		public Child(Long id) {
+			this.id = id;
+		}
+
+		@Override
+		public Long getId() {
+			return this.id;
+		}
+	}
+}