Add test to check if private constructors lead to meaningful error messages when using bytecode enhancement

hibernate-core/src/test/java/org/hibernate/jpa/test/callbacks/PrivateConstructorEnhancerTest.java

@@ -0,0 +1,188 @@
+/*
+ * 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.callbacks;
+
+import java.util.List;
+import javax.persistence.Basic;
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+import org.hibernate.engine.spi.SessionFactoryImplementor;
+
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+@RunWith(BytecodeEnhancerRunner.class)
+public class PrivateConstructorEnhancerTest extends BaseNonConfigCoreFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class<?>[] {
+				Person.class,
+				Country.class
+		};
+	}
+
+	private Country country = new Country( "Romania" );
+	private Person person = new Person( "Vlad Mihalcea", country );
+
+	@Override
+	protected void afterSessionFactoryBuilt(SessionFactoryImplementor sessionFactory) {
+		doInHibernate( this::sessionFactory, session -> {
+			session.persist( country );
+
+			session.persist( person );
+		} );
+	}
+
+	@Test
+	public void testFindEntity() {
+
+		doInHibernate( this::sessionFactory, session -> {
+			try {
+				Country country = session.find( Country.class, this.country.id );
+
+				assertNotNull( "Romania", country.getName() );
+				fail( "Should have thrown exception" );
+			}
+			catch (Exception expected) {
+				assertTrue( expected.getMessage().contains( "No default constructor for entity" ) );
+			}
+		} );
+	}
+
+	@Test
+	public void testGetReferenceEntity() {
+
+		doInHibernate( this::sessionFactory, session -> {
+			try {
+				Country country = session.getReference( Country.class, this.country.id );
+
+				assertNotNull( "Romania", country.getName() );
+				fail( "Should have thrown exception" );
+			}
+			catch (Exception expected) {
+				assertTrue( expected.getMessage().contains( "No default constructor for entity" ) );
+			}
+		} );
+	}
+
+	@Test
+	public void testLoadProxyAssociation() {
+
+		doInHibernate( this::sessionFactory, session -> {
+			try {
+				Person person = session.find( Person.class, this.person.id );
+
+				assertNotNull( "Romania", person.getCountry().getName() );
+				fail( "Should have thrown exception" );
+			}
+			catch (Exception expected) {
+				assertTrue( expected.getMessage().contains( "No default constructor for entity" ) );
+			}
+		} );
+	}
+
+	@Test
+	public void testListEntity() {
+
+		doInHibernate( this::sessionFactory, session -> {
+			try {
+				List<Person> persons = session.createQuery( "select p from Person p" ).getResultList();
+				assertTrue( persons.stream().anyMatch( p -> p.getCountry().getName().equals( "Romania" ) ) );
+
+				fail( "Should have thrown exception" );
+			}
+			catch (Exception expected) {
+				assertTrue( expected.getMessage().contains( "No default constructor for entity" ) );
+			}
+		} );
+	}
+
+	@Test
+	public void testListJoinFetchEntity() {
+
+		doInHibernate( this::sessionFactory, session -> {
+			try {
+				List<Person> persons = session.createQuery( "select p from Person p join fetch p.country" )
+						.getResultList();
+				assertTrue( persons.stream().anyMatch( p -> p.getCountry().getName().equals( "Romania" ) ) );
+
+				fail( "Should have thrown exception" );
+			}
+			catch (Exception expected) {
+				assertTrue( expected.getMessage().contains( "No default constructor for entity" ) );
+			}
+		} );
+	}
+
+	@Entity(name = "Person")
+	private static class Person {
+
+		@Id
+		@GeneratedValue
+		private int id;
+
+		private String name;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		private Country country;
+
+		public Person() {
+		}
+
+		private Person(String name, Country country) {
+			this.name = name;
+			this.country = country;
+		}
+
+		public int getId() {
+			return id;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public Country getCountry() {
+			return country;
+		}
+	}
+
+	@Entity(name = "Country")
+	private static class Country {
+
+		@Id
+		@GeneratedValue
+		private int id;
+
+		@Basic(fetch = FetchType.LAZY)
+		private String name;
+
+		private Country(String name) {
+			this.name = name;
+		}
+
+		public int getId() {
+			return id;
+		}
+
+		public String getName() {
+			return name;
+		}
+	}
+}