Java tutorial
/** * Abiquo community edition * cloud management application for hybrid clouds * Copyright (C) 2008-2010 - Abiquo Holdings S.L. * * This application is free software; you can redistribute it and/or * modify it under the terms of the GNU LESSER GENERAL PUBLIC * LICENSE as published by the Free Software Foundation under * version 3 of the License * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * LESSER GENERAL PUBLIC LICENSE v.3 for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ package com.abiquo.server.core.common.persistence; import java.io.Serializable; import java.util.List; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import org.hibernate.Criteria; import org.hibernate.criterion.Criterion; import org.hibernate.criterion.Order; import org.hibernate.criterion.Projections; import org.hibernate.criterion.Restrictions; import org.springframework.transaction.support.TransactionSynchronizationManager; import com.abiquo.server.core.common.GenericEnityBase; import com.softwarementors.bzngine.dao.hibernate.JpaHibernateDaoBase; import com.softwarementors.bzngine.entities.PersistentEntity; public abstract class DefaultDAOBase<I extends Serializable, T extends GenericEnityBase<I>> extends JpaHibernateDaoBase<T, I> { private boolean managed; @PersistenceContext @Override protected void setEntityManager(final EntityManager entityManager) { super.setEntityManager(entityManager); } /* default constructor for Spring */ protected DefaultDAOBase(final Class<T> persistentClass) { super(persistentClass); this.managed = true; } /* * @SuppressWarnings("deprecation") public Connection getConnection() { return * getSession().connection(); } */ protected DefaultDAOBase(final Class<T> persistentClass, final EntityManager entityManager) { super(persistentClass, entityManager); } // TODO: PAG, fix this by changing parameter type for base class isManaged public boolean isManaged2(final PersistentEntity<?> entity) { assert entity != null; assert isOpen(); assert isInTransaction(); return entity.getId() != null && getEntityManager().contains(entity); } @Override public boolean isInTransaction() { if (!managed) { return super.isInTransaction(); } return TransactionSynchronizationManager.isActualTransactionActive(); } @Override public boolean isInReadWriteTransaction() { if (!managed) { return super.isInReadWriteTransaction(); } return !TransactionSynchronizationManager.isCurrentTransactionReadOnly(); } @Override public boolean isInRollbackTransaction() { if (!managed) { return super.isInRollbackTransaction(); } return !TransactionSynchronizationManager.isSynchronizationActive(); } public T findUniqueByProperty(final String propertyName, final String value) { Criterion criterion = Restrictions.eq(propertyName, value); return findUniqueByCriterions(criterion); } protected Criteria createNestedCriteria(final String... propertyNames) { Criteria crit = getSession().createCriteria(getPersistentClass()); return createNestedCriteria(crit, propertyNames); } protected Criteria createNestedCriteria(final Order order, final String... propertyNames) { Criteria crit = getSession().createCriteria(getPersistentClass()); crit.addOrder(order); return createNestedCriteria(crit, propertyNames); } private Criteria createNestedCriteria(final Criteria baseCriteria, final String... propertyNames) { Criteria crit = baseCriteria; for (String property : propertyNames) { crit = crit.createCriteria(property); } return crit; } protected Long count() { Criteria criteria = getSession().createCriteria(getPersistentClass()); return count(criteria); } protected Long count(final Criteria criteria) { criteria.setProjection(Projections.rowCount()); return (Long) criteria.uniqueResult(); } protected T getSingleResultOrNull(final Criteria criteria) { List<T> results = getResultList(criteria); return (results == null || results.isEmpty()) ? null : results.get(0); } public void detach(final T entity) { this.getEntityManager().detach(entity); } }