package com.cns.certservice.dao.impl;
import org.apache.log4j.Logger;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import com.cns.certservice.exception.DAOException;
public class HibernateTemplate {
private HibernateTemplate() {
}
/**
* static final session factory
*/
private static SessionFactory sessionFactory = null;
/**
* local thread variable used for storing share session instance
*/
private static final ThreadLocal localSession = new ThreadLocal();
/**
* log4j logger
*/
private static final Logger logger = Logger
.getLogger(HibernateTemplate.class);
/**
* use JTA transaction
*/
/**
* 该工具唯一实例。
*/
private static HibernateTemplate instance = null;
private static Transaction tx = null;
private static String CONFIG_FILE_LOCATION = “/hibernate.cfg.xml”;
private static final Configuration cfg = new Configuration();
/** Holds a single instance of Session */
private static final ThreadLocal threadLocal = new ThreadLocal();
/**
* 获取持久工具的唯一实例，以后不是使用单实例模式，而不是采用对象池支持。
* @return PersistentTool
* @throws BaseException
*/
public synchronized static HibernateTemplate getInstance() {
if (instance == null) {
instance = new HibernateTemplate();
instance.initHibernate();
}
return instance;
}
/**
* 实现Hibernate的初始化配置环境。
*/
public void initHibernate() {
try {
//此处从系统路径中获取配置文件
cfg.configure(CONFIG_FILE_LOCATION);
} catch (HibernateException ex) {
ex.printStackTrace();
}
try {
// 装载配置，构造SessionFactory对象
sessionFactory = cfg.buildSessionFactory();
} catch (HibernateException e) {
e.printStackTrace();
}
}
/**
* Get the share session
* @
* @return Session share session
*/
public Session getSession() {
logger.debug(”Now enter into getSession method of DaoUtil”);
//obtain share session
Session session = (Session) localSession.get();
try {
if (session == null||!session.isOpen()) {
//get session by session factory
session = sessionFactory.openSession();
localSession.set(session);
}
} catch (HibernateException ex) {
ex.printStackTrace();
}
return session;
}
/**
* Close share session
* @
*/
public void close() {
logger.debug(”Now enter into closeSessionl”);
//obtain share session
Session session = (Session) localSession.get();
localSession.set(null);
if (session != null) {
try {
session.flush();
session.close();
} catch (HibernateException ex) {
ex.printStackTrace();
}
}
}
/**
* Begin JTA transaction
* @
*/
public void beginTransaction() {
logger.debug(”Now enter into beginTransaction”);
try {
Session session = (Session) localSession.get();
tx = session.beginTransaction();
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Commit transaction
* @
*/
public void commitTransaction() {
try {
tx.commit();
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Rollback transaction when breaching ACID operation
* @
*/
public void rollbackTransaction() {
try {
tx.rollback();
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Insert a record into table
* @param obj Object
* @throws DAOException
* @
*/
public int insertObject(Object obj) throws DAOException {
int res = 0;
logger.debug(”Now enter into insertObject”);
//obtain current share session
try {
Session session = HibernateTemplate.getInstance().getSession();
beginTransaction();
Object robj = session.save(obj);
if (robj instanceof Integer) {
res = (Integer) robj;
}
if (robj instanceof String) {
res =1;
}
session.flush();
} catch (HibernateException ex) {
rollbackTransaction();
logger.error(”insertObject error:”, ex);
throw new DAOException(ex);
} finally {
commitTransaction();
close();
}
return res;
}
/**
* Delete a record of database table by Hibernate po object
* @param obj Object
* @throws DAOException
* @
*/
public boolean deleteObject(Object obj) throws DAOException {
boolean res = false;
logger.debug(”Now enter into deleteObject method”);
//obtain current share session
try {
Session session = HibernateTemplate.getInstance().getSession();
beginTransaction();
session.delete(obj);
session.flush();
res = true;
} catch (HibernateException ex) {
rollbackTransaction();
logger.error(”deleteObject error:”, ex);
throw new DAOException(ex);
} finally {
commitTransaction();
close();
}
return res;
}
/**
* Update a record of database table
* @param ob Object
* @throws DAOException
* @
*/
public boolean updateObject(Object ob) throws DAOException {
boolean res = false;
logger.debug(”Now enter into updateObject”);
//obtain current share session
try {
Session session = HibernateTemplate.getInstance().getSession();
beginTransaction();
session.update(ob);
session.flush();
res= true;
} catch (HibernateException ex) {
rollbackTransaction();
logger.error(”updateObject error:”, ex);
throw new DAOException(ex);
} finally {
commitTransaction();
close();
}
return res;
}
}
