问调用百度图像检测接口返回json数据？

import java.util.*;

/**
 * easydl物体检测
 */
public class EasydlObjectDetection {

    /**
     * 重要提示代码中所需工具类
     * FileUtil,Base64Util,HttpUtil,GsonUtils请从
     * https://ai.baidu.com/file/658A35ABAB2D404FBF903F64D47C1F72
     * https://ai.baidu.com/file/C8D81F3301E24D2892968F09AE1AD6E2
     * https://ai.baidu.com/file/544D677F5D4E4F17B4122FBD60DB82B3
     * https://ai.baidu.com/file/470B3ACCA3FE43788B5A963BF0B625F3
     * 下载
     */
    public static String easydlObjectDetection() {
        // 请求url
        String url = "https://aip.baidubce.com/rpc/2.0/ai_custom/v1/detection/cuochuangsb";
        try {
            Map<String, Object> map = new HashMap<>();
            map.put("image", "");

            String param = GsonUtils.toJson(map);

            // 注意这里仅为了简化编码每一次请求都去获取access_token，线上环境access_token有过期时间， 客户端可自行缓存，过期后重新获取。
            String accessToken = "24.5bc282fb48f48c80cd38948a273279e0.2592000.1650028827.282335-25774089";

            String result = HttpUtil.post(url, accessToken, "application/json", param);
            System.out.println(result);
            return result;