HHH-9403 - AssertionFailure: Fail to process type argument in a generic declaration

hibernate-core/src/main/java/org/hibernate/metamodel/internal/AttributeFactory.java

@@ -11,6 +11,7 @@ import java.lang.reflect.Member;
 import java.lang.reflect.Method;
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.TypeVariable;
+import java.lang.reflect.WildcardType;
 import java.util.Iterator;
 import javax.persistence.ManyToMany;
 import javax.persistence.OneToOne;
@@ -878,6 +879,10 @@ public class AttributeFactory {
 				final java.lang.reflect.Type rawType = ( (ParameterizedType) type ).getRawType();
 				return getClassFromGenericArgument( rawType );
 			}
+			else if ( type instanceof WildcardType ) {
+				final java.lang.reflect.Type upperBound = ( (WildcardType) type ).getUpperBounds()[0];
+				return getClassFromGenericArgument( upperBound );
+			}
 			else {
 				throw new AssertionFailure(
 						"Fail to process type argument in a generic declaration. Member : " + getMemberDescription()

hibernate-core/src/test/java/org/hibernate/test/metamodel/WildcardTypeAttributeMetaModelTest.java

@@ -0,0 +1,43 @@
+/*
+ * 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.test.metamodel;
+
+import javax.persistence.metamodel.EntityType;
+
+import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.test.metamodel.wildcardmodel.AbstractEntity;
+import org.hibernate.test.metamodel.wildcardmodel.AbstractOwner;
+import org.hibernate.test.metamodel.wildcardmodel.EntityOne;
+import org.hibernate.test.metamodel.wildcardmodel.OwnerOne;
+import org.junit.Test;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
+import static org.junit.Assert.assertNotNull;
+
+public class WildcardTypeAttributeMetaModelTest extends BaseEntityManagerFunctionalTestCase {
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] {
+				AbstractEntity.class,
+				AbstractOwner.class,
+				EntityOne.class,
+				OwnerOne.class
+		};
+	}
+
+	@Test
+	@TestForIssue(jiraKey = "HHH-9403")
+	public void testWildcardGenericAttributeCanBeResolved() {
+		doInJPA( this::entityManagerFactory, entityManager -> {
+			EntityType<AbstractOwner> entity = entityManager.getMetamodel().entity( AbstractOwner.class );
+			assertNotNull( entity );
+		} );
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/metamodel/wildcardmodel/AbstractEntity.java

@@ -0,0 +1,43 @@
+/*
+ * 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.test.metamodel.wildcardmodel;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.ManyToOne;
+
+@Entity
+@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
+public abstract class AbstractEntity {
+
+	@Id
+	@GeneratedValue
+	private Long id;
+
+	@ManyToOne()
+	private AbstractOwner owner;
+
+	public Long getId() {
+		return id;
+	}
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public AbstractOwner getOwner() {
+		return owner;
+	}
+
+	public void setOwner(AbstractOwner owner) {
+		this.owner = owner;
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/metamodel/wildcardmodel/AbstractOwner.java

@@ -0,0 +1,47 @@
+/*
+ * 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.test.metamodel.wildcardmodel;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.persistence.CascadeType;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.OneToMany;
+
+@Entity
+@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
+public abstract class AbstractOwner {
+
+	@Id
+	@GeneratedValue
+	private Long id;
+
+    @OneToMany(cascade = CascadeType.ALL, mappedBy = "owner", targetEntity = AbstractEntity.class)
+	private List<? extends AbstractEntity> entities = new ArrayList<>();
+
+	public Long getId() {
+		return id;
+	}
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public List<? extends AbstractEntity> getEntities() {
+		return entities;
+	}
+
+	public void setEntities(List<? extends AbstractEntity> entities) {
+		this.entities = entities;
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/test/metamodel/wildcardmodel/EntityOne.java

@@ -0,0 +1,14 @@
+/*
+ * 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.test.metamodel.wildcardmodel;
+
+import javax.persistence.Entity;
+
+@Entity
+public class EntityOne extends AbstractEntity {
+
+}

hibernate-core/src/test/java/org/hibernate/test/metamodel/wildcardmodel/OwnerOne.java

@@ -0,0 +1,20 @@
+/*
+ * 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.test.metamodel.wildcardmodel;
+
+import java.util.List;
+import javax.persistence.Entity;
+
+@Entity
+public class OwnerOne extends AbstractOwner {
+
+	@SuppressWarnings("unchecked")
+	@Override
+	public List<EntityOne> getEntities() {
+		return (List<EntityOne>) super.getEntities();
+	}
+}