万能Map

作为parameter：将map的key和value映射到parameter
　　List<User> getUserListByLimit(Map<String,Object> map);
　　<select id="getUserListByLimit" parameterType="map" resultType="user">
    select * from user where id limit #{startIndex},#{pageSize}
　　</select>
　　@Test
　　public void getUserListByLimit() {
  　　  UserMapper mapper = session.getMapper(UserMapper.class);
  　　  HashMap<String, Object> map = new HashMap<>();
  　　  map.put("startIndex", 0);
   　　 map.put("pageSize", 2);
   　　 for (User user : mapper.getUserListByLimit(map)) {
    　　   logger.info(user);
 　　   }
  　　  session.close();
　　}

作为result:查询结果为一个对象
    HashMap<String, Object> getStudentById(int id);
    <select id="getStudentById" resultType="map" parameterType="int">
    select * from student where id = #{id}
    </select>

    @Test
    public void getStudentById(){
        StudentMapper mapper = session.getMapper(StudentMapper.class);
        HashMap<String, Object> map = mapper.getStudentById(1);
        for (String s : map.keySet()) {
            System.out.println(s+" : "+map.get(s));
        }
    }