/* * 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.cascade; import javax.persistence.EntityManager; import javax.persistence.EntityTransaction; import org.junit.Test; import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase; /** * @author Max Rydahl Andersen */ public class CascadeTest extends BaseEntityManagerFunctionalTestCase { @Test public void testCascade() throws Exception { EntityManager em = getOrCreateEntityManager(); em.getTransaction().begin(); Teacher teacher = new Teacher(); Student student = new Student(); teacher.setFavoriteStudent(student); student.setFavoriteTeacher(teacher); teacher.getStudents().add(student); student.setPrimaryTeacher(teacher); em.persist( teacher ); em.getTransaction().commit(); em = getOrCreateEntityManager(); em.getTransaction().begin(); Teacher foundTeacher = (Teacher) em.createQuery( "select t from Teacher as t" ).getSingleResult(); System.out.println(foundTeacher); System.out.println(foundTeacher.getFavoriteStudent()); for (Student fstudent : foundTeacher.getStudents()) { System.out.println(fstudent); System.out.println(fstudent.getFavoriteTeacher()); System.out.println(fstudent.getPrimaryTeacher()); } em.getTransaction().commit(); // here *alot* of flushes occur on an object graph that has *Zero* changes. em.close(); } @Test public void testNoCascadeAndMerge() throws Exception { Song e1 = new Song(); Author e2 = new Author(); e1.setAuthor(e2); EntityManager em = getOrCreateEntityManager(); EntityTransaction tx = em.getTransaction(); tx.begin(); em.persist(e2); em.persist(e1); tx.commit(); em.close(); em = getOrCreateEntityManager(); e1 = em.find(Song.class, e1.getId()); tx = em.getTransaction(); tx.begin(); em.merge(e1); //em.refresh(e1); tx.commit(); em.close(); } @Override public Class[] getAnnotatedClasses() { return new Class[]{ Teacher.class, Student.class, Song.class, Author.class }; } }