java调用http接口问题

在第三方开店卖商品，我需要把我查到的数据用post形式发给第三方接口！！不会弄啊，
各位哥哥能帮帮我吗http://open.mengdian.com/doc/api/tag/zb_list.html

public static String postDataUTF8(Map<String,String> data, String url)
{

    HttpClient httpClient = new HttpClient();
    HttpConnectionManagerParams managerParams = httpClient
            .getHttpConnectionManager().getParams();
    // 设置连接超时时间(单位毫秒)
    managerParams.setConnectionTimeout(connectionTimeout);
    // 设置读数据超时时间(单位毫秒)
    managerParams.setSoTimeout(soTimeout);
    PostMethodUTF8 postMethod = new PostMethodUTF8(url);
    Iterator<String> it = data.keySet().iterator();

    NameValuePair[] sendData = new NameValuePair[data.keySet().size()];
    int i = 0;
    String key = "";
    while(it.hasNext())
    {
        key = it.next();
        sendData[i++] = new NameValuePair(key, data.get(key));
    }

    postMethod.setRequestBody(sendData);
    postMethod.setRequestHeader("Content-Type","application/x-www-form-urlencoded;charset=UTF-8"); 
    String strResponse = null;
    try {
        int statusCode = httpClient.executeMethod(postMethod);
        //logger.info("--------Connect the interface at time:" + new Date());
        if (statusCode != HttpStatus.SC_OK) {
            strResponse = "error_第三方返回非200状态码";
            throw new IllegalStateException("Method failed: "
                    + postMethod.getStatusLine());
        }
        strResponse = postMethod.getResponseBodyAsString();
        if(NetCheckFieldsUtil.isBlank(strResponse)){
            strResponse = "error_第三方返回空数据";
        }
        //System.out.println("getResponseCharSet:"+postMethod.getResponseCharSet());
        //System.out.println("getRequestCharSet:"+postMethod.getRequestCharSet());
    }catch(UnsupportedEncodingException e){
        e.printStackTrace();
        logger.error("UnsupportedEncodingException:",e);
        strResponse = "error_发生UnsupportedEncodingException异常,未能成功调用第三方";
    }catch(IllegalStateException e){
        e.printStackTrace();
        logger.error("IllegalStateException:",e);

// strResponse = "error_发生IllegalStateException异常,未能成功调用第三方";
} catch (ConnectTimeoutException e) {
// System.out.println("time out");
e.printStackTrace();
// throw new java.net.SocketTimeoutException("time out");
logger.error("ConnectTimeoutException:",e);
strResponse = "error_请求第三方时发生ConnectTimeoutException异常";
} catch(SocketTimeoutException e){
e.printStackTrace();
logger.error("SocketTimeoutException:",e);
strResponse = "error_请求第三方时发生SocketTimeoutException异常";
}catch (Exception ex) {
ex.printStackTrace();
// throw new IllegalStateException(ex.toString());
logger.error("Exception:",ex);
strResponse = "error_请求第三方时发生未知异常";
} finally {
postMethod.releaseConnection();
}
//logger.info(strResponse);
return strResponse;
}

以这个接口为例：http://open.mengdian.com/doc/apiarticle/tag/Ib_doc

string json=" { "category_id": "538112937", "category_attr_name": "品牌", "category_attr_values": [ "苹果", "三星", "HTC" ] }";

string url="https://open.mengdian.com/api/mname/WE_MALL/cname/categoryattributeAdd?accesstoken=ACCESS_TOKEN";//这是萌店开放平台的地址

public static final MediaType JSON = MediaType.parse("application/json; charset=utf-8");
OkHttpClient client = new OkHttpClient();
String post(String url, String json) throws IOException {
RequestBody body = RequestBody.create(JSON, json);
Request request = new Request.Builder()
.url(url)
.post(body)
.build();
Response response = client.newCall(request).execute();
if (response.isSuccessful()) {
return response.body().string();
//这里返回的结果就是实例返回的json字符串
} else {
throw new IOException("Unexpected code " + response);
}
}