删除

  @Test
    public void testRemove(){
        //1.通过工具类获取entityManager
        EntityManager entityManager = JpaUtils.getEntityManager();
        //2.开启事务
        EntityTransaction transaction = entityManager.getTransaction();
        transaction.begin();
        //3.增删改查 -- 删除客户
        // i.根据id查询客户
        Customer customer = entityManager.find(Customer.class, 1l);
        // ii：调用remove方法完成删除操作
        entityManager.remove(customer);
        //4.提交事务
        transaction.commit();
        //5.释放资源
        entityManager.close();
    }