001    // Copyright 2007, 2008 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.tynamo.jpa.internal;
016    
017    import javax.persistence.EntityManager;
018    import javax.persistence.EntityTransaction;
019    
020    import org.apache.tapestry5.ioc.services.ThreadCleanupListener;
021    
022    import org.tynamo.jpa.JPAEntityManagerSource;
023    import org.tynamo.jpa.JPATransactionManager;
024    
025    public class JPATransactionManagerImpl implements JPATransactionManager, ThreadCleanupListener
026    {
027            private final EntityManager entityManager;
028    
029            private EntityTransaction transaction;
030    
031            public JPATransactionManagerImpl(JPAEntityManagerSource source)
032            {
033                    entityManager = source.create();
034    
035                    startNewTransaction();
036            }
037    
038            private void startNewTransaction()
039            {
040                    // transaction = session.beginTransaction();
041                    transaction = entityManager.getTransaction();
042                    transaction.begin();
043            }
044    
045            public void abort()
046            {
047                    transaction.rollback();
048                    startNewTransaction();
049            }
050    
051            public void commit()
052            {
053                    transaction.commit();
054                    startNewTransaction();
055            }
056    
057            public EntityManager getEntityManager()
058            {
059                    return entityManager;
060            }
061    
062            /**
063             * Rollsback the transaction at the end of the request, then closes the session. This means that
064             * any uncommitted changes are lost; code should inject the HSM and invoke {@link #commit()}
065             * after making any changes, if they should persist.
066             */
067            public void threadDidCleanup()
068            {
069                    transaction.rollback();
070    
071                    entityManager.close();
072            }
073    }