封装HibernateUtil对象

package org.cric.util;

import java.io.Serializable;
import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {
	
	private static SessionFactory factory=null;
	
	//静态方法,只实例化一次,因为SessionFactory重量级,每个SessionFactory对应一个数据库,包含这个数据库的全部信息
	//单实例!
	static{
		try{
			Configuration cfg=new Configuration().configure();
			factory=cfg.buildSessionFactory();
		}catch(Exception e){
			e.printStackTrace();
		}
	}
	//获取Session 对象
	public static Session getSession(){
		return factory.openSession();
	}
	//获取SessionFactory对象
	public static SessionFactory getSessionFactory(){
		return factory;
	}
	//因为Session 不是线程安全的,所以需要关闭
	public static void closeSession(Session session){
		if(session!=null){
			if(session.isOpen()){
				session.close();
			}
		}
	}
	//封装save方法
	public static Integer save(Object object){
		Integer status=0;
		Session session=null;
		Transaction tr=null;
		try{
			session=HibernateUtil.getSession();
			tr=session.beginTransaction();
			Serializable serializable=session.save(object);
			status=serializable.hashCode();//序列化转化成Integer类型
			tr.commit();
			return status;
		}
		catch(Exception e){
			e.printStackTrace();
			tr.rollback();
			throw new RuntimeException();
		}finally{
			HibernateUtil.closeSession(session);
		}
	}
	//封装update方法
	public static Integer update(Object object){
		Session session=null;
		Transaction tr=null;
		try{
			session=HibernateUtil.getSession();
			tr=session.beginTransaction();
			session.update(object);
			tr.commit();
			return 1;
		}catch(Exception e){
			e.printStackTrace();
			tr.rollback();
			throw new RuntimeException();
		}finally{
			HibernateUtil.closeSession(session);
		}
	}
	//封装delete方法
	public static Integer delete(Object object){
		Session session=null;
		Transaction tr=null;
		try{
			session=HibernateUtil.getSession();
			tr=session.beginTransaction();
			session.delete(object);
			tr.commit();
			return 1;
		}catch(Exception e){
			e.printStackTrace();
			tr.rollback();
			throw new RuntimeException();
		}finally{
			HibernateUtil.closeSession(session);
		}
	}
	//封装get方法
	public static Object get(Class<?> clazz,Integer id){
		Session session=null;
		Transaction tr=null;
		try{
			session=HibernateUtil.getSession();
			tr=session.beginTransaction();
			Object obj=session.get(clazz, id);
			tr.commit();
			return obj;
		}catch(Exception e){
			e.printStackTrace();
			tr.rollback();
			throw new RuntimeException();
		}finally{
			HibernateUtil.closeSession(session);
		}
	}
	//封装find方法
	public static List<?> find(String HQL){
		Session session=null;
		Transaction tr=null;
		List<?> list=null;
		try{
			session=HibernateUtil.getSession();
			tr=session.beginTransaction();
			Query query=session.createQuery(HQL);
			list=query.list();
			tr.commit();
			return list;
		}catch(Exception e){
			e.printStackTrace();
			tr.rollback();
			throw new RuntimeException();
		}finally{
			HibernateUtil.closeSession(session);
		}
	}
}