java里怎么解析mybatis返回的单条map类型集合？

Question

上图是数据表查询，返回Map类型的XML映射写法

上图写了个@MapKey注解，不写会报错

这是最终调试的参数值，是个单条Map类型，有动态的key，有value,value是一个单条数据表记录集合，
这个怎么解析呢？无论我尝试了多种途径，都不好用，
我用fastjson解析也不行。
请教大神！

---

我尝试的操作

//获取登陆用户的id和openid
        Map<String, Object> wxUserInfo = wxLoginMapper.getWxUserByOpenidInfo(params.getOpenId());
        String jsonString = "";
        for(String key : wxUserInfo.keySet()){
            jsonString = JSON.toJSONString(wxUserInfo.get(key));
        }
        log.info(jsonString);

code: 500
message: "操作失败，java.lang.Integer cannot be cast to java.lang.String"
result: null
success: false
timestamp: 1735821282293

针对回答 **

解析出来是这样子的，我主要想获取openid的值，这个字符串怎么获取openid的值呢，关键前面的key是动态的？

Answer 1

思路排查

Mapper接口和XML配置：

public interface WxLoginMapper {
    Map<String, Object> getWxUserByOpenidInfo(String openId);
}

<select id="getWxUserByOpenidInfo" resultType="java.util.HashMap">
    SELECT * FROM yy_xx WHERE openid=#{openId}
</select>

添加fastjson依赖：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.83</version>
</dependency>

在Spring Boot应用中使用Mapper，在Service类中解析JSON字符串并提取openid的值：

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Service
public class WxLoginService {
    private static final Logger log = LoggerFactory.getLogger(WxLoginService.class);

    @Autowired
    private WxLoginMapper wxLoginMapper;

    public void logWxUserInfo(String openId) {
        Map<String, Object> wxUserInfo = wxLoginMapper.getWxUserByOpenidInfo(openId);
        String jsonString = JSON.toJSONString(wxUserInfo);

        // 解析JSON字符串为JSONObject
        JSONObject jsonObject = JSON.parseObject(jsonString);

        // 获取动态key的第一个值
        String dynamicKey = jsonObject.keySet().iterator().next();
        JSONObject innerObject = jsonObject.getJSONObject(dynamicKey);

        // 获取openid的值
        String openid = innerObject.getString("openid");

        // 输出openid
        log.info("OpenID: " + openid);
    }
}

在Controller中调用Service：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class WxLoginController {
    @Autowired
    private WxLoginService wxLoginService;

    @GetMapping("/logWxUserInfo")
    public ResponseEntity<Void> logWxUserInfo(@RequestParam String openId) {
        wxLoginService.logWxUserInfo(openId);
        return ResponseEntity.ok().build();
    }
}