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.eagerset.SetChild; import com.vladmihalcea.hibernate.model.eagerset.SetParent; 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 HibernateSaveIdOnlyEntityTest { private static final Logger LOG = LoggerFactory.getLogger(HibernateSaveIdOnlyEntityTest.class); @PersistenceContext(unitName = "persistenceUnit") private EntityManager entityManager; @Autowired private TransactionTemplate transactionTemplate; @Test public void test() { final Long parentId = cleanAndSaveParent(); SetParent parent = transactionTemplate.execute(new TransactionCallback<SetParent>() { @Override public SetParent doInTransaction(TransactionStatus transactionStatus) { SetParent parent = loadParent(parentId); SetChild child1 = new SetChild(); child1.setName("child1"); SetChild child2 = new SetChild(); child2.setName("child2"); parent.addChild(child1); parent.addChild(child2); entityManager.merge(parent); return parent; } }); transactionTemplate.execute(new TransactionCallback<Void>() { @Override public Void doInTransaction(TransactionStatus transactionStatus) { SetParent idOnlyParent = new SetParent(); idOnlyParent.setId(parentId); SetChild newChild = new SetChild(); newChild.setName("new"); newChild.setParent(idOnlyParent); entityManager.persist(newChild); entityManager.flush(); SetChild otherChild = new SetChild(); otherChild.setName("Other"); idOnlyParent.addChild(otherChild); entityManager.flush(); assertEquals(1, idOnlyParent.getChildren().size()); return null; } }); transactionTemplate.execute(new TransactionCallback<Void>() { @Override public Void doInTransaction(TransactionStatus transactionStatus) { SetParent parent = entityManager.find(SetParent.class, parentId); assertEquals(3, parent.getChildren().size()); return null; } }); } protected Long cleanAndSaveParent() { return transactionTemplate.execute(new TransactionCallback<Long>() { @Override public Long doInTransaction(TransactionStatus transactionStatus) { entityManager.createQuery("delete from SetChild where id > 0").executeUpdate(); entityManager.createQuery("delete from SetParent where id > 0").executeUpdate(); assertTrue(entityManager.createQuery("from SetParent").getResultList().isEmpty()); SetParent parent = new SetParent(); entityManager.persist(parent); entityManager.flush(); return parent.getId(); } }); } protected SetParent loadParent(Long parentId) { //return entityManager.createQuery("from SetParent where id =:parentId", SetParent.class).setParameter("parentId", parentId).getSingleResult(); return entityManager.find(SetParent.class, parentId); } }