Mybatis 使用HashMap 传参parameterType

客官°小女子只卖身不卖艺 2023-06-18 06:56 1阅读 0赞

**parameterType指定HashMap传递输入参数，“\#\{\}”和“$\{\}”中自动识别Map的key，并替换参数**

SQL映射文件定义如下：传入的参数类型是HashMap

<select id="selectUserByHashmap"
        parameterType="hashmap" resultType="user">
            select * from user where id=#{id} and username like '%${username}%'
        </select>

1、在UserMapper.xml中添加如下SQL

<select id="findUserListByMap" parameterType="hashmap"
            resultType="UserCustom">
            select * from user where user.sex = #{sex}
                and user.username like '%${username}%'
        </select>

2、在UserMapper.java中定义如下方法

/**
        * 使用HashMap作为参数查询结果集
        * @param param
        * @return
        * @throws Exception
        */
        List<UserCustom> findUserListByMap(Map<String, String> param) throws Exception;

3、编写测试方法进行测试

/**
        * 使用HashMap作为参数查询结果集
        * @throws Exception
        */
        @Test
        public void testFindUserListByMap() throws Exception{
            SqlSession sqlSession = sqlSessionFactory.openSession();
            //创建UserMapper对象,mybatis自动生成mapper代理对象
            UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
            //组装查询条件
            Map<String, String> param = new HashMap<String, String>();
            param.put("sex", "1");
            param.put("username", "张");
            List<UserCustom> users = userMapper.findUserListByMap(param);
            System.out.println(users);
        }