13-jpql查询-分页查询

    /*
    分页查询
        sql：select * from cst_customer limit 0,2
        jpql: from Customer
     */
    @Test
    public void testPaged(){
        EntityManager entityManager = JpaUtils.getEntityManager();
        EntityTransaction tx = entityManager.getTransaction();
        tx.begin();

        //查询全部
        //根据jpsql语句创建query查询对象
        String jpql = "from Customer";
        Query query = entityManager.createQuery(jpql);
        /*
        对参数进行赋值---分页参数
         */
        //起始索引
        query.setFirstResult(0);
        //每页查询的条数
        query.setMaxResults(2);

        //发送查询，并封装结果
        List list = query.getResultList();
        for (Object o : list) {
            System.out.println(o);
        }

        tx.commit();
        entityManager.close();
    }