/*  *具体操作hibernate的类  *增加,删除,修改,按ID查询,模糊查询,查询全部  **/ public class PersonOperate {  //在hibernate中所有操作都是由Session完成  public Session session = null;   //在构造方法中实例化Session对象  public PersonOperate(){      //找出hibernate的配置      Configuration config = new Configuration().configure();      //从配置中取出SessionFactory      SessionFactory sf = config.buildSessionFactory();      //从SessionFactory中取出Session      this.session = sf.openSession();  }   //操作Hibernate类的所有操作都是通过Session完成的   //增加数据库中数据  public void insert(Person person){      //开始事务      Transaction tran =    session.beginTransaction();      //执行语句      session.save(person);      //提交事务      tran.commit();      session.close();   }   //操作Hibernate类更改数据库中的数据  public void update(Person person){      //开始事务      Transaction tran =    session.beginTransaction();      //执行语句      session.update(person);      //提交事务      tran.commit();   }   /*操作Hibernate类：按ID查询      *我们插入,修改都是对对象进行操作      *那么我们查询的时候也应该是返回一个对象      **/ public Person queryById(String id){      System.out.println(id);      Person person = null;      //hibernate查询语句      String hql = "FROM Person as p WHERE p.id = ?";      Query q = session.createQuery(hql);      q.setString(0, id);      List list = q.list();      Iterator iteator = list.iterator();      if(iteator.hasNext()){       person = (Person)iteator.next();      }      return person;  }   /*操作Hibernate类：删除数据库中数据      *hiberante2,hibernate3中通用的删除方法      *缺点:删除数据之前要先查询一次数据,找出删除的数据对象      *性能低下      **/ public void delete(Person person){      //开始事务      Transaction tran =    session.beginTransaction();      //执行语句      session.delete(person);      //提交事务      tran.commit();   }   //hibernate3的用法  public void delete(String id){      //开始事务      Transaction tran =    session.beginTransaction();      String hql = "DELETE Person WHERE id = ?";       Query q = session.createQuery(hql);      q.setString(0, id);      //执行更新语句      q.executeUpdate();      //提交事务      tran.commit();  }   //操作Hibernate类：查询全部数据  public List queryAll(){      List list = null;      String hql = "FROM Person as p ";      Query q = session.createQuery(hql);      list = q.list();      return list;  }   //操作Hibernate类：模糊查询  public List queryByLike(String colnum,String value){      List list = null;      String hql = "FROM Person as p WHERE p."+ colnum +" like ?";      Query q = session.createQuery(hql);      q.setString(0, "%"+ value +"%");      list = q.list();  

Criteria criteria = session.createCriteria(Customer.class);Criterion c1 = Expression.like("name", "T%");Criterion c2 = Exception.eq("age", new Long(21));criteria.add(c1);criteria.add(c2);List list = criteria.list();以上语句相当于：    List list = session..createCriteria(Customer.class)                .add(Expression.like("name", "T%"))                .add(Exception.eq("age", new Long(21)))                .list();                查询List <User> user = session.createCriteria(User.class)                         //必需创建一个别名，roles为user中包 含的role 的list.                         .createAlias("roles","roles")                         //roleId为传进来进行查询的角色ID                         .add(Restrictions.eq("roles.id",roleId))                         .list();