Java tutorial
/* * Copyright 2002-2004 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 org.springframework.autobuilds.ejbtest.hibernate.tx.ejb; import java.sql.SQLException; import javax.ejb.CreateException; import javax.ejb.SessionBean; import javax.ejb.SessionContext; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.springframework.autobuilds.ejbtest.Constants; import org.springframework.context.access.ContextSingletonBeanFactoryLocator; import org.springframework.dao.DataAccessException; import org.springframework.dao.DataRetrievalFailureException; import org.springframework.ejb.support.AbstractStatelessSessionBean; import org.springframework.orm.hibernate3.HibernateCallback; import org.springframework.orm.hibernate3.HibernateTemplate; import org.springframework.orm.hibernate3.SessionFactoryUtils; /** * <p>EJB used just to test proper Hibernate Session binding and unbinding in * a CMT (Container Managed Transaction) environment with JTA, but no Spring * TransactionManager involved. The methods here are not an example of what your * own EJB methods should do; they are just meant to test that Spring internals * are working ok. However the config of this bean _is_ a general example of how * you would set up an EJB to work with CMT without Spring transaction environment</p> * * <p>In a CMT without Spring transactions environment, as long as the Hibernate * Configuration is set up with a TransactionManagerLookup so Hibernate (and Spring) * can find the JTA TransactionManager, Spring is still able to bind the Hibernate * Session to the current transaction, and ensure that all Hibernate work in a * transaction happens within the same session (when using * HibernateTemplate/SessionFactoryUtils.</p> * * <p>This is not an example of how you would ideally write an EJB in a Spring * environment. Ideally the EJB just obtains a POJO service object (wrapped with * TransactionInterceptor and possibly HibernateInterceptor) from an * ApplicationContext, and delegates all method calls to it. The technique used * here though is useful when there is a need to keep actual business code in the * EJB, and have this code work with Hibernate/Spring Mappers/DAOs. * </p> * * @author colin sampaleanu */ public class CmtJtaNoSpringTxEJB extends AbstractStatelessSessionBean implements SessionBean, CmtJtaNoSpringTx { // --- statics public static final String SESSION_FACTORY_ID = "hibSessionFactory"; protected static final Log logger = LogFactory.getLog(CmtJtaNoSpringTxEJB.class); // --- attributes SessionFactory sessionFactory; /* * (non-Javadoc) * * @see javax.ejb.SessionBean#setSessionContext(javax.ejb.SessionContext) */ public void setSessionContext(SessionContext sessionContext) { super.setSessionContext(sessionContext); setBeanFactoryLocator(ContextSingletonBeanFactoryLocator.getInstance()); setBeanFactoryLocatorKey(Constants.SERVICE_LAYER_CONTEXT_ID); } /* * arghhh! stupid method needed just to make XDoclet happy, otherwise it will * create one in the subclass it generates, killing the one in the superclass * @ejb.create-method */ public void ejbCreate() throws CreateException { super.ejbCreate(); } // javadoc in superclass protected void onEjbCreate() throws CreateException { sessionFactory = (SessionFactory) getBeanFactory().getBean(SESSION_FACTORY_ID); } // javadoc in superclass public String echo(String input) { return "hello " + input; } // javadoc in superclass public void testSameSessionReceivedInTwoRequests() throws TestFailureException { Session sess1 = SessionFactoryUtils.getSession(sessionFactory, true); Session sess2 = SessionFactoryUtils.getSession(sessionFactory, true); if (sess1 != sess2) throw new TestFailureException( "Should have received the same Session in each execute call since we are in one JTA transaction, but they were different."); sess1.close(); } public void throwExceptionSoSessionUnbindCanBeVerified() throws DataAccessException { HibernateTemplate h = new HibernateTemplate(sessionFactory, true); h.execute(new HibernateCallback() { public Object doInHibernate(Session session) throws HibernateException, SQLException { return session; } }); h.execute(new HibernateCallback() { public Object doInHibernate(Session session) throws HibernateException, SQLException { throw new DataRetrievalFailureException( "This Exception is being thrown just to verify proper unbinding of Hibernate Session from JTA transaction"); } }); } }