/*
* This file is part of LibrePlan
*
* Copyright (C) 2009-2010 Fundación para o Fomento da Calidade Industrial e
* Desenvolvemento Tecnolóxico de Galicia
* Copyright (C) 2010-2011 Igalia, S.L.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.libreplan.business.common.daos;
import java.io.Serializable;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.util.List;
import org.apache.commons.lang3.Validate;
import org.hibernate.Hibernate;
import org.hibernate.LockMode;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.StaleObjectStateException;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.libreplan.business.common.BaseEntity;
import org.libreplan.business.common.exceptions.InstanceNotFoundException;
import org.libreplan.business.common.exceptions.ValidationException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.transaction.annotation.Transactional;
/**
* An implementation of <code>IGenericDao</code> based on Hibernate's native API.
* Concrete DAOs must extend directly from this class.
* This constraint is imposed by the constructor of this class that must infer the type of the
* entity from the declaration of the concrete DAO.
*
* This class autowires a <code>SessionFactory</code> bean and allows to implement DAOs with Hibernate's native API.
* Subclasses access Hibernate's <code>Session</code> by calling on <code>getSession()</code> method.
* Operations must be implemented by catching <code>HibernateException</code>
* and rethrowing it by using <code>convertHibernateAccessException()</code> method.
* See source code of this class for an example.
*
* @author Fernando Bellas Permuy <fbellas@udc.es>
* @param <E>
* Entity class
* @param <PK>
* Primary key class
*/
public class GenericDAOHibernate<E extends BaseEntity, PK extends Serializable> implements IGenericDAO<E, PK> {
private Class<E> entityClass;
@Autowired
private SessionFactory sessionFactory;
@SuppressWarnings("unchecked")
public GenericDAOHibernate() {
this.entityClass =
(Class<E>) ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
}
public GenericDAOHibernate(Class<E> entityClass) {
Validate.notNull(entityClass);
this.entityClass = entityClass;
}
protected Session getSession() {
return sessionFactory.getCurrentSession();
}
public Class<E> getEntityClass() {
return entityClass;
}
/**
* It's necessary to save and validate later.
*
* Validate may retrieve the entity from DB and put it into the Session, which can eventually lead to
* a NonUniqueObject exception.
* Save works here to reattach the object as well as saving.
*/
public void save(E entity) throws ValidationException {
getSession().saveOrUpdate(entity);
entity.validate();
}
public void saveWithoutValidating(E entity) {
getSession().saveOrUpdate(entity);
}
public void reattachUnmodifiedEntity(E entity) {
if ( Hibernate.isInitialized(entity) && entity.isNewObject() ) {
return;
}
// TODO resolve deprecated
getSession().lock(entity, LockMode.NONE);
}
public E merge(E entity) {
return entityClass.cast(getSession().merge(entity));
}
public void checkVersion(E entity) {
/* Get id and version from entity */
Serializable id;
Long versionValueInMemory;
try {
Method getIdMethod = entityClass.getMethod("getId");
id = (Serializable) getIdMethod.invoke(entity);
if ( id == null ) {
return;
}
Method getVersionMethod = entityClass.getMethod("getVersion");
versionValueInMemory = (Long) getVersionMethod.invoke(entity);
if ( versionValueInMemory == null ) {
return;
}
} catch (Exception e) {
throw new RuntimeException(e);
}
/* Check version */
Long versionValueInDB = (Long) getSession()
.createCriteria(entityClass)
.add(Restrictions.idEq(id))
.setProjection(Projections.property("version"))
.uniqueResult();
if ( versionValueInDB == null ) {
return;
}
if ( !versionValueInMemory.equals(versionValueInDB) ) {
throw new StaleObjectStateException(entityClass.getName(), id);
}
}
public void lock(E entity) {
// TODO resolve deprecated
getSession().lock(entity, LockMode.UPGRADE);
}
@SuppressWarnings("unchecked")
@Transactional(readOnly = true)
public E find(PK id) throws InstanceNotFoundException {
E entity = (E) getSession().get(entityClass, id);
if ( entity == null ) {
throw new InstanceNotFoundException(id, entityClass.getName());
}
return entity;
}
public E findExistingEntity(PK id) {
try {
return find(id);
} catch (InstanceNotFoundException e) {
throw new RuntimeException(e);
}
}
public boolean exists(final PK id) {
return getSession()
.createCriteria(entityClass)
.add(Restrictions.idEq(id))
.setProjection(Projections.id())
.uniqueResult() != null;
}
public void remove(PK id) throws InstanceNotFoundException {
getSession().delete(find(id));
}
@SuppressWarnings("unchecked")
@Override
@Transactional(readOnly = true)
public <T extends E> List<T> list(Class<T> klass) {
return getSession().createCriteria(klass).list();
}
@Override
public void flush() {
getSession().flush();
}
@Override
@Transactional
public void reattach(E entity) {
getSession().saveOrUpdate(entity);
}
}