mybatis通过多个参数查询

public interface UserDao {
   
     User finMap(Map map);
}
-------------------------------------

<select id="finMap" resultType="pojo.User">
    select * from user where id=#{id} and username=#{username} and age=#{age}
</select>
---------------------------------------

--------------通过Map集合查询（可以单个参数也可以多个参数）-----------------------------
      Map map=new HashMap<>();
        map.put("id",1);
        map.put("username","UZI");
        map.put("age",19);

        User user1 = userDao.finMap(map);

        System.out.println(user1);
        session.close();
    }
}


--------------多个参数查询，通过注解@——————————————————————————————————————————————-——————

User findtwo(@Param("id") int id, @Param("username") String username);

----------------------------------------------------------------------------------

<select id="findtwo" resultType="pojo.User">
    select * from user where id=#{id} and username=#{username}
</select>
------------------------------------------------------------------------------------

User user = userDao.findtwo(2, "PDD");
System.out.println(user);
session.close();
------------------------------------------------------------------------------
（为什么多参数会报错，设计时候源码只写了一个 obj 多个参数时候会封装成一个Map对象 agr或者param作为key值）


--------------插入操作----------------------------------------------------------------

void insertUser(User user); （这边不需要返回值，不然会报错）

insert id="insertUser">
    insert  into  user values (#{id},#{username},#{age},#{address})
</insert>

userDao.insertUser(new User(3,"若风",35,"黑龙江"));

session.close();