HHH-8802 - Class cast exception thrown when trying to access Embedded type relationship path in Tuple

hibernate-entitymanager/src/main/java/org/hibernate/jpa/criteria/path/SingularAttributeJoin.java

@@ -9,7 +9,10 @@ package org.hibernate.jpa.criteria.path;
 import javax.persistence.criteria.JoinType;
 import javax.persistence.metamodel.Attribute;
 import javax.persistence.metamodel.Bindable;
+import javax.persistence.metamodel.ManagedType;
+import javax.persistence.metamodel.PluralAttribute;
 import javax.persistence.metamodel.SingularAttribute;
+import javax.persistence.metamodel.Type;
 
 import org.hibernate.jpa.criteria.CriteriaBuilderImpl;
 import org.hibernate.jpa.criteria.CriteriaSubqueryImpl;
@@ -36,13 +39,17 @@ public class SingularAttributeJoin<O,X> extends AbstractJoinImpl<O,X> {
 			SingularAttribute<? super O, ?> joinAttribute,
 			JoinType joinType) {
 		super( criteriaBuilder, javaType, pathSource, joinAttribute, joinType );
-		this.model = (Bindable<X>) (
-				Attribute.PersistentAttributeType.EMBEDDED == joinAttribute.getPersistentAttributeType()
-						? joinAttribute
-						: javaType != null
-						? criteriaBuilder.getEntityManagerFactory().getMetamodel().managedType( javaType )
-						: joinAttribute.getType()
-		);
+		if ( Attribute.PersistentAttributeType.EMBEDDED == joinAttribute.getPersistentAttributeType() ) {
+			this.model = (Bindable<X>) joinAttribute;
+		}
+		else {
+			if ( javaType != null ) {
+				this.model = (Bindable<X>) criteriaBuilder.getEntityManagerFactory().getMetamodel().managedType( javaType );
+			}
+			else {
+				this.model = (Bindable<X>) joinAttribute.getType();
+			}
+		}
 	}
 
 	@Override
@@ -71,6 +78,34 @@ public class SingularAttributeJoin<O,X> extends AbstractJoinImpl<O,X> {
 		return true;
 	}
 
+	@Override
+	@SuppressWarnings("unchecked")
+	protected ManagedType<? super X> locateManagedType() {
+		if ( getModel().getBindableType() == Bindable.BindableType.ENTITY_TYPE ) {
+			return (ManagedType<? super X>) getModel();
+		}
+		else if ( getModel().getBindableType() == Bindable.BindableType.SINGULAR_ATTRIBUTE ) {
+			final Type joinedAttributeType = ( (SingularAttribute) getAttribute() ).getType();
+			if ( !ManagedType.class.isInstance( joinedAttributeType ) ) {
+				throw new UnsupportedOperationException(
+						"Cannot further dereference attribute join [" + getPathIdentifier() + "] as its type is not a ManagedType"
+				);
+			}
+			return (ManagedType<? super X>) joinedAttributeType;
+		}
+		else if ( getModel().getBindableType() == Bindable.BindableType.PLURAL_ATTRIBUTE ) {
+			final Type elementType = ( (PluralAttribute) getAttribute() ).getElementType();
+			if ( !ManagedType.class.isInstance( elementType ) ) {
+				throw new UnsupportedOperationException(
+						"Cannot further dereference attribute join [" + getPathIdentifier() + "] (plural) as its element type is not a ManagedType"
+				);
+			}
+			return (ManagedType<? super X>) elementType;
+		}
+
+		return super.locateManagedType();
+	}
+
 	public Bindable<X> getModel() {
 		return model;
 	}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/criteria/components/joins/ComponentJoinTest.java

@@ -0,0 +1,114 @@
+/*
+ * 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.jpa.test.criteria.components.joins;
+
+import java.util.List;
+import javax.persistence.EntityManager;
+import javax.persistence.Tuple;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Join;
+import javax.persistence.criteria.JoinType;
+import javax.persistence.criteria.Path;
+import javax.persistence.criteria.Root;
+import javax.persistence.metamodel.SingularAttribute;
+
+import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class ComponentJoinTest extends BaseEntityManagerFunctionalTestCase {
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] { Entity.class, EmbeddedType.class, ManyToOneType.class };
+	}
+
+	public static final String THEVALUE = "thevalue";
+
+	@Before
+	public void before() {
+		EntityManager entityManager = entityManagerFactory().createEntityManager();
+		entityManager.getTransaction().begin();
+		ManyToOneType manyToOneType = new ManyToOneType( THEVALUE );
+		EmbeddedType embeddedType = new EmbeddedType( manyToOneType );
+		Entity entity = new Entity( embeddedType );
+		entityManager.persist( entity );
+		entityManager.getTransaction().commit();
+		entityManager.close();
+	}
+	
+	@After
+	public void after() {
+		EntityManager entityManager = entityManagerFactory().createEntityManager();
+		entityManager.getTransaction().begin();
+		entityManager.createQuery( "delete Entity" ).executeUpdate();
+		entityManager.createQuery( "delete ManyToOneType" ).executeUpdate();
+		entityManager.getTransaction().commit();
+		entityManager.close();
+	}
+
+	interface JoinBuilder {
+		Join<EmbeddedType,ManyToOneType> buildJoinToManyToOneType(Join<Entity, EmbeddedType> source);
+	}
+
+	private void doTest(JoinBuilder joinBuilder) {
+		EntityManager entityManager = getOrCreateEntityManager();
+		entityManager.getTransaction().begin();
+
+		CriteriaBuilder builder = entityManager.getCriteriaBuilder();
+		CriteriaQuery<Tuple> criteriaQuery = builder.createTupleQuery();
+		Root<Entity> root = criteriaQuery.from( Entity.class );
+		Join<Entity, EmbeddedType> join = root.join( "embeddedType", JoinType.LEFT );
+
+		// left join to the manyToOne on the embeddable with a string property
+		Path<String> path = joinBuilder.buildJoinToManyToOneType( join ).get( "value" );
+
+		// select the path in the tuple
+		criteriaQuery.select( builder.tuple( path ) );
+
+		List<Tuple> results = entityManager.createQuery( criteriaQuery ).getResultList();
+		Tuple result = results.iterator().next();
+
+		assertEquals( THEVALUE, result.get(0) );
+
+		entityManager.getTransaction().commit();
+		entityManager.close();
+	}
+
+	@Test
+	public void getResultWithStringPropertyDerivedPath() {
+		doTest(
+				new JoinBuilder() {
+					@Override
+					public Join<EmbeddedType, ManyToOneType> buildJoinToManyToOneType(Join<Entity, EmbeddedType> source) {
+						return source.join( "manyToOneType", JoinType.LEFT );
+					}
+				}
+		);
+	}
+	
+	@Test
+	@SuppressWarnings("unchecked")
+	public void getResultWithMetamodelDerivedPath() {
+		doTest(
+				new JoinBuilder() {
+					@Override
+					public Join<EmbeddedType, ManyToOneType> buildJoinToManyToOneType(Join<Entity, EmbeddedType> source) {
+						final SingularAttribute<EmbeddedType, ManyToOneType> attr =
+								(SingularAttribute<EmbeddedType, ManyToOneType>) entityManagerFactory().getMetamodel()
+										.managedType( EmbeddedType.class )
+										.getDeclaredSingularAttribute( "manyToOneType" );
+						return source.join( attr, JoinType.LEFT );
+					}
+				}
+		);
+	}
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/criteria/components/joins/EmbeddedType.java

@@ -0,0 +1,36 @@
+/*
+ * 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.jpa.test.criteria.components.joins;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Embeddable;
+import javax.persistence.ManyToOne;
+
+/**
+ * @author Matt Todd
+ */
+@Embeddable
+public class EmbeddedType {
+	@ManyToOne(cascade = CascadeType.ALL)
+	private ManyToOneType manyToOneType;
+
+	public EmbeddedType() {
+	}
+
+	public EmbeddedType(ManyToOneType manyToOneType) {
+		this.manyToOneType = manyToOneType;
+	}
+
+	public ManyToOneType getManyToOneType() {
+		return manyToOneType;
+	}
+
+	public void setManyToOneType(ManyToOneType manyToOneType) {
+		this.manyToOneType = manyToOneType;
+	}
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/criteria/components/joins/Entity.java

@@ -0,0 +1,37 @@
+/*
+ * 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.jpa.test.criteria.components.joins;
+
+import javax.persistence.Embedded;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+@javax.persistence.Entity
+public class Entity {
+	@Id
+	@GeneratedValue
+	private Long id;
+
+	@Embedded
+	private EmbeddedType embeddedType;
+
+	public Entity() {
+		// for jpa
+	}
+
+	public Entity(EmbeddedType embeddedType) {
+		this.embeddedType = embeddedType;
+	}
+
+	public EmbeddedType getEmbeddedType() {
+		return embeddedType;
+	}
+
+	public void setEmbeddedType(EmbeddedType embeddedType) {
+		this.embeddedType = embeddedType;
+	}
+}

hibernate-entitymanager/src/test/java/org/hibernate/jpa/test/criteria/components/joins/ManyToOneType.java

@@ -0,0 +1,37 @@
+/*
+ * 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.jpa.test.criteria.components.joins;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+/**
+ * @author Matt Todd
+ */
+@Entity
+public class ManyToOneType {
+	@Id
+	@GeneratedValue
+	public Long id;
+	private String value;
+
+	public ManyToOneType() {
+	}
+
+	public ManyToOneType(String value) {
+		this.value = value;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public void setValue(String value) {
+		this.value = value;
+	}
+}