Java tutorial
/* * Copyright 2013 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.vladmihalcea; import com.vladmihalcea.hibernate.model.bag.Child; import com.vladmihalcea.hibernate.model.bag.Parent; import org.junit.Test; import org.junit.runner.RunWith; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.test.annotation.DirtiesContext; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import org.springframework.transaction.TransactionStatus; import org.springframework.transaction.support.TransactionCallback; import org.springframework.transaction.support.TransactionTemplate; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertTrue; @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations = { "classpath:spring/applicationContext-test.xml" }) @DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_CLASS) public class HibernateBagDuplicateTest { private static final Logger LOG = LoggerFactory.getLogger(HibernateBagDuplicateTest.class); @PersistenceContext(unitName = "persistenceUnit") private EntityManager entityManager; @Autowired private TransactionTemplate transactionTemplate; @Test public void test() { final Long parentId = cleanAndSaveParent(); Parent parent = transactionTemplate.execute(new TransactionCallback<Parent>() { @Override public Parent doInTransaction(TransactionStatus transactionStatus) { Parent parent = loadParent(parentId); Child child1 = new Child(); child1.setName("child1"); Child child2 = new Child(); child2.setName("child2"); parent.addChild(child1); parent.addChild(child2); entityManager.merge(parent); entityManager.flush(); if (parent.getChildren().size() == 4) { LOG.error("Duplicates rows generated!"); } return parent; } }); //https://hibernate.atlassian.net/browse/HHH-3332 //https://hibernate.atlassian.net/browse/HHH-5855 //assertEquals(2, parent.getChildren().size()); if (parent.getChildren().size() == 4) { LOG.error("Duplicates rows generated!"); } transactionTemplate.execute(new TransactionCallback<Void>() { @Override public Void doInTransaction(TransactionStatus transactionStatus) { assertEquals(4, loadParent(parentId).getChildren().size()); return null; } }); } @Test public void testFixByPersistingChild() { final Long parentId = cleanAndSaveParent(); Parent parent = transactionTemplate.execute(new TransactionCallback<Parent>() { @Override public Parent doInTransaction(TransactionStatus transactionStatus) { Parent parent = loadParent(parentId); Child child1 = new Child(); child1.setName("child1"); Child child2 = new Child(); child2.setName("child2"); entityManager.persist(child1); entityManager.persist(child2); parent.addChild(child1); parent.addChild(child2); entityManager.merge(parent); parent.getChildren().size(); return parent; } }); assertEquals(2, parent.getChildren().size()); } protected Long cleanAndSaveParent() { return transactionTemplate.execute(new TransactionCallback<Long>() { @Override public Long doInTransaction(TransactionStatus transactionStatus) { entityManager.createQuery("delete from Child where id > 0").executeUpdate(); entityManager.createQuery("delete from Parent where id > 0").executeUpdate(); assertTrue(entityManager.createQuery("from Parent").getResultList().isEmpty()); Parent parent = new Parent(); entityManager.persist(parent); entityManager.flush(); return parent.getId(); } }); } protected Parent loadParent(Long parentId) { return entityManager.find(Parent.class, parentId); } }