Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 org.apache.openjpa.persistence.event; import javax.persistence.EntityManager; import javax.persistence.EntityTransaction; import javax.persistence.Query; import org.apache.commons.lang.StringUtils; import org.apache.openjpa.event.TransactionEvent; import org.apache.openjpa.event.TransactionListener; import org.apache.openjpa.jdbc.conf.JDBCConfiguration; import org.apache.openjpa.jdbc.sql.DBDictionary; import org.apache.openjpa.jdbc.sql.OracleDictionary; import org.apache.openjpa.jdbc.sql.SybaseDictionary; import org.apache.openjpa.persistence.OpenJPAEntityManagerFactorySPI; import org.apache.openjpa.persistence.OpenJPAEntityManagerSPI; import org.apache.openjpa.persistence.test.AbstractPersistenceTestCase; public class TestBeforeCommit extends AbstractPersistenceTestCase implements TransactionListener { AnEntity ae = null; public final int PKID = 2; private DBDictionary dict = null; private static OpenJPAEntityManagerFactorySPI emf = null; @Override public void setUp() throws Exception { if (emf == null) { emf = createEMF(AnEntity.class); } dict = ((JDBCConfiguration) emf.getConfiguration()).getDBDictionaryInstance(); EntityManager em = emf.createEntityManager(); EntityTransaction tran = em.getTransaction(); tran.begin(); em.createQuery("Delete from AnEntity").executeUpdate(); tran.commit(); tran.begin(); ae = new AnEntity(); ae.setId(PKID); ae.setName(""); em.persist(ae); tran.commit(); em.close(); } @Override public void tearDown() throws Exception { closeEMF(emf); emf = null; super.tearDown(); } public void testQuery() { OpenJPAEntityManagerSPI em = (OpenJPAEntityManagerSPI) emf.createEntityManager(); em.addTransactionListener(this); EntityTransaction tran = em.getTransaction(); tran.begin(); ae = doQuery(em); if (dict instanceof OracleDictionary) { assertNull(ae.getName()); } else if (dict instanceof SybaseDictionary) { // Sybase converts empty strings to " " assertEquals(" ", ae.getName()); } else { assertEquals("", ae.getName()); } assertEquals(1, ae.getVersion()); tran.commit(); ae = doQuery(em); assertEquals("Ava", ae.getName()); assertEquals(2, ae.getVersion()); em.clear(); ae = em.find(AnEntity.class, PKID); assertEquals("Ava", ae.getName()); assertEquals(2, ae.getVersion()); tran.begin(); tran.commit(); em.clear(); ae = em.find(AnEntity.class, PKID); assertEquals("AvaAva", ae.getName()); assertEquals(3, ae.getVersion()); em.close(); } public void testEmptyTransaction() { OpenJPAEntityManagerSPI em = (OpenJPAEntityManagerSPI) emf.createEntityManager(); em.addTransactionListener(this); EntityTransaction tran = em.getTransaction(); ae = doQuery(em); if (dict instanceof OracleDictionary) { assertNull(ae.getName()); } else if (dict instanceof SybaseDictionary) { // Sybase converts "" to " " assertEquals(" ", ae.getName()); } else { assertEquals("", ae.getName()); } assertEquals(1, ae.getVersion()); em.clear(); tran.begin(); tran.commit(); // when BeforeCommit was fired AE was not managed. As a result its state is out of sync with the database. assertEquals("Ava", ae.getName()); ae = doQuery(em); if (dict instanceof OracleDictionary) { assertNull(ae.getName()); } else if (dict instanceof SybaseDictionary) { assertEquals(" ", ae.getName()); } else { assertEquals("", ae.getName()); } assertEquals(1, ae.getVersion()); em.close(); } public void beforeCommit(TransactionEvent event) { if (StringUtils.isBlank(ae.getName())) { ae.setName("Ava"); } else { ae.setName(ae.getName() + "Ava"); } } private AnEntity doQuery(EntityManager em) { Query q = em.createQuery("select a from AnEntity a where a.id = :id"); return (AnEntity) q.setParameter("id", PKID).getSingleResult(); } // Unused Interface methods public void afterBegin(TransactionEvent event) { } public void afterFlush(TransactionEvent event) { } public void beforeFlush(TransactionEvent event) { } public void afterCommit(TransactionEvent event) { } public void afterCommitComplete(TransactionEvent event) { } public void afterRollback(TransactionEvent event) { } public void afterRollbackComplete(TransactionEvent event) { } public void afterStateTransitions(TransactionEvent event) { } }