hibernate之工具类HibernateUtil

1.最简单的工具类，实现SessionFactory的单例共享，session的管理

package com.cc.hibernate;



import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.Configuration;

import org.hibernate.service.ServiceRegistry;

import org.hibernate.service.ServiceRegistryBuilder;



public class HibernateUtil {

    //创建工厂类，是静态的单例的，只能被赋值一次

    private static final SessionFactory sessionFactory=buildSessionFactory();

    /** init sessionFactory */

    private static SessionFactory buildSessionFactory(){

        SessionFactory sessionFactory=null;

        try{

            //configure函数里面可以写hibernate的配置文件，空则默认为hibernate.cfg.xml

            Configuration configuration=new Configuration().configure();

            ServiceRegistry serviceRegistry=new ServiceRegistryBuilder().applySettings(configuration.getProperties()).buildServiceRegistry();

            sessionFactory= configuration.buildSessionFactory(serviceRegistry);

        }

        catch(Throwable te){

            System.err.println("init sessionFactory Error:"+te);

            te.printStackTrace();

        }

        return sessionFactory;

    }

    /** get session */

    public static Session getSession(){

        //得到session

        Session session=sessionFactory.openSession();

        return session;

    }

}

2.将常见事务方法封装进工具类

添加如下方法：

//删除

public static boolean delete(Object obj){  

    Session session=null;  

    Transaction tran=null;  

    boolean result=false;  

    try{  

        session=getSession();  

        tran=session.beginTransaction();  

        session.delete(obj);  

        tran.commit();  

        result=true;  

    }  

    catch (Exception e){  

        if(tran!=null){  

            //事物回滚  

            tran.rollback();  

        }  

    }  

    finally{  

        if(session!=null){  

            //关闭session  

            session.close();  

        }  

    }  

    return result;  

} 

//更新

public static boolean update(Object object)  

{  

    Session session=null;  

    Transaction tran=null;  

    boolean result=false;  

    try{  

        session=getSession();  

        tran=session.beginTransaction();  

        session.update(object);  

        tran.commit();  

        result=true;  

    }  

    catch (Exception e){  

        if(tran!=null){  

            //事物回滚  

            tran.rollback();  

        }  

    }  

    finally{  

        if(session!=null){  

            //关闭session  

            session.close();  

        }  

    }  

    return result;  

} 

//增加

public static boolean add(Object obj){  

    Session session=null;  

    Transaction tran=null;  

    boolean result=false;  

    try{  

        session=getSession();  

        tran=session.beginTransaction();  

        session.save(obj);  

        tran.commit();  

        result=true;  

    }  

    catch (Exception e){  

       if(tran!=null){  

           //事物回滚  

           tran.rollback();  

       }  

    }  

    finally  

    {  

        if(session!=null){  

            //关闭session  

            session.close();  

        }  

    }  

    return result;  

}

//执行sql语句，返回单条记录

public static Object queryOne(String sql,String[] param){  

    Object object=null;  

    Session session=null;  

    try{  

        session=getSession();  

        Query query=session.createQuery(sql);  

        if(param!=null){  

            for(int i=0;i<param.length;i++){  

                query.setString(0,param[i]);      

            }  

            object=query.uniqueResult();  

        }  

    }  

    catch (Exception e){  

    }  

    finally{  

        if(session!=null){  

            session.close();  

        }  

    }  

    return object;  

}   

参考：http://blog.csdn.net/hanhan313/article/details/8125924