根据经纬度获取百度cityCode java代码

以下是使用Java代码实现的示例：

import java.io.IOException;
import java.net.URLEncoder;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

public class BaiduMapUtils {

    /**
     * 根据经纬度获取百度cityCode
     * @param lng 经度
     * @param lat 纬度
     * @param ak 百度地图API密钥
     * @return 百度cityCode
     * @throws IOException
     */
    public static String getCityCode(double lng, double lat, String ak) throws IOException {
        String url = "http://api.map.baidu.com/reverse_geocoding/v3/";
        String location = lat + "," + lng;
        String params = "ak=" + ak + "&output=json&coordtype=wgs84ll&location=" + URLEncoder.encode(location, "UTF-8");
        String result = doGet(url, params);
        JSONObject json = JSON.parseObject(result);
        if (json.getIntValue("status") == 0) {
            JSONObject addressComponent = json.getJSONObject("result").getJSONObject("addressComponent");
            String cityCode = addressComponent.getString("cityCode");
            return StringUtils.isNotEmpty(cityCode) ? cityCode : "";
        }
        return "";
    }

    /**
     * 发送GET请求
     * @param url 请求地址
     * @param params 请求参数
     * @return 响应内容
     * @throws IOException
     */
    private static String doGet(String url, String params) throws IOException {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpGet httpGet = new HttpGet(url + "?" + params);
        CloseableHttpResponse response = null;
        try {
            response = httpClient.execute(httpGet);
            HttpEntity entity = response.getEntity();
            if (entity != null) {
                return EntityUtils.toString(entity, "UTF-8");
            }
        } finally {
            if (response != null) {
                response.close();
            }
        }
        return "";
    }
}

调用示例：

public class Test {
    public static void main(String[] args) throws IOException {
        double lng = 116.404;
        double lat = 39.915;
        String ak = "你的百度地图API密钥";
        String cityCode = BaiduMapUtils.getCityCode(lng, lat, ak);
        System.out.println(cityCode);
    }
}

注意：需要替换代码中的百度地图API密钥。