java代码post请求参数map字符串

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

public static void main(String[] args) {
    Map<String,String> map=new HashMap();
    map.put("start","0");
    map.put("limit","10");
    String param= JSON.toJSONString(map);
   //JSONObject object=JSON.parseObject(JSON.toJSONString(map))

    String postValue =  sendPost(url, param,8*1000,10*1000, Charset.forName("utf-8"));
    System.out.println(postValue);
}

public static String sendPost(String url, String param,int connectTimeout,int readTimeout, Charset charset)  {
    try {
        URL httpurl = new URL(url);
        HttpURLConnection httpConn = (HttpURLConnection) httpurl.openConnection();
        httpConn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; "
                + "Windows NT 5.1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
        httpConn.setConnectTimeout(8 * 1000);
        httpConn.setReadTimeout(10 * 1000);
        httpConn.setDoOutput(true);
        httpConn.setDoInput(true);
        httpConn.setUseCaches(false);
        httpConn.setRequestMethod("POST");
        httpConn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded;charset=" + charset.name());
        httpConn.connect();
        OutputStream outputStream = httpConn.getOutputStream();
        PrintWriter out = new PrintWriter(outputStream);
        out.print(param);
        out.flush();
        out.close();
        InputStream inputStream = httpConn.getInputStream();
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, charset.name()));
        StringBuffer stringBuffer = new StringBuffer();
        String line = null;
        while ((line = bufferedReader.readLine()) != null) {
            stringBuffer.append(line);
        }
        String resp = stringBuffer.toString();
       // System.out.println(resp);
        if (stringBuffer != null) {
            try {
                bufferedReader.close();
            } catch (IOException var18) {
                var18.printStackTrace();
            }
        }
        if (inputStream != null) {
            try {
                inputStream.close();
            } catch (IOException var17) {
                var17.printStackTrace();
            }
        }
        if (outputStream != null) {
            try {
                outputStream.close();
            } catch (IOException var17) {
                var17.printStackTrace();
            }
        }
        return resp;
    }catch (IOException e) {
        throw new RuntimeException(String.format("url:%s,param:%s,message:%s", url, param, e.getMessage()), e);
    }
}