001    /**
002     *
003     * Licensed to the Apache Software Foundation (ASF) under one or more
004     * contributor license agreements.  See the NOTICE file distributed with
005     * this work for additional information regarding copyright ownership.
006     * The ASF licenses this file to You under the Apache License, Version 2.0
007     * (the "License"); you may not use this file except in compliance with
008     * the License.  You may obtain a copy of the License at
009     *
010     * http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    package org.apache.camel.component.jpa;
019    
020    import org.apache.camel.impl.ServiceSupport;
021    import org.springframework.orm.jpa.JpaCallback;
022    import org.springframework.orm.jpa.JpaTemplate;
023    import org.springframework.orm.jpa.JpaTransactionManager;
024    import org.springframework.transaction.TransactionStatus;
025    import org.springframework.transaction.support.TransactionCallback;
026    import org.springframework.transaction.support.TransactionTemplate;
027    
028    import javax.persistence.EntityManager;
029    import javax.persistence.EntityManagerFactory;
030    import javax.persistence.PersistenceException;
031    
032    /**
033     * Delegates the strategy to the {@link JpaTemplate} and {@link TransactionTemplate} for transaction handling
034     *
035     * @version $Revision: 525537 $
036     */
037    public class JpaTemplateTransactionStrategy extends ServiceSupport implements TransactionStrategy {
038        private final JpaTemplate jpaTemplate;
039        private final TransactionTemplate transactionTemplate;
040    
041        /**
042         * Creates a new implementation from the given JPA factory
043         */
044        public static JpaTemplateTransactionStrategy newInstance(EntityManagerFactory emf) {
045            JpaTemplate template = new JpaTemplate(emf);
046            return newInstance(emf, template);
047        }
048    
049        public static JpaTemplateTransactionStrategy newInstance(EntityManagerFactory emf, JpaTemplate template) {
050            JpaTransactionManager transactionManager = new JpaTransactionManager(emf);
051            transactionManager.afterPropertiesSet();
052    
053            TransactionTemplate tranasctionTemplate = new TransactionTemplate(transactionManager);
054            tranasctionTemplate.afterPropertiesSet();
055    
056            return new JpaTemplateTransactionStrategy(template, tranasctionTemplate);
057        }
058    
059        public JpaTemplateTransactionStrategy(JpaTemplate jpaTemplate, TransactionTemplate transactionTemplate) {
060            this.jpaTemplate = jpaTemplate;
061            this.transactionTemplate = transactionTemplate;
062        }
063    
064        public Object execute(final JpaCallback callback) {
065            return transactionTemplate.execute(new TransactionCallback() {
066                public Object doInTransaction(TransactionStatus status) {
067                    return jpaTemplate.execute(new JpaCallback() {
068                        public Object doInJpa(EntityManager entityManager) throws PersistenceException {
069                            return callback.doInJpa(entityManager);
070                        }
071                    });
072                }
073            });
074        }
075    
076        protected void doStart() throws Exception {
077        }
078    
079        protected void doStop() throws Exception {
080        }
081    }