//is empty and is not empty

    @Test

    public void testQBC(){

        Session session = sf.getCurrentSession();

        session.beginTransaction();

        //criterion 标准/准则/规范

        Criteria c = session.createCriteria(Topic.class)//from Topic

                .add(Restrictions.gt("id", 2))    //greater than = id > 2

                .add(Restrictions.lt("id", 8))    //less than = id < 8

                .add(Restrictions.like("title", "t_"))

                .createCriteria("category")

                .add(Restrictions.between("id", 0, 5)) //category.id >= 0 and category.id <= 5

                ;

        //DetachedCriteria

        for(Object o : c.list()){

            Topic t = (Topic)o;

            System.out.println(t.getId() + "-" + t.getTitle() );

        }

        session.getTransaction().commit();

    }

     //is empty and is not empty

     //QBC Query By Criteria

     //QBE Query By Example

     @Test

     public void testQBE(){

         Session session = sf.getCurrentSession();

         session.beginTransaction();

         Topic tExample = new Topic();

         tExample.setTitle("T_");

         Example e = Example.create(tExample)

                 .ignoreCase().enableLike();//构建 example

         Criteria c = session.createCriteria(Topic.class)

                 .add(Restrictions.gt("id", 3))

                 .add(Restrictions.lt("id", 8))

                 .add(e)

                 ;

         for(Object o : c.list()){

             Topic t = (Topic)o;

             System.out.println(t.getId() + "-" + t.getTitle() );

         }

         session.getTransaction().commit();

     }