HTTP Post请求并在Java中解析响应

Question

我正在尝试为Web API创建一个简单的发布请求并解析收到的响应。经过大量的搜索，我能够得到以下代码：

public class access {

public static void main(String[] args) {


    HttpClient httpclient = HttpClients.createDefault();
    HttpPost httppost = new HttpPost("https://xxxxx/RSAM_API/api/Logon");

    httppost.setHeader("Accept", "application/json");
    httppost.setHeader("Content-type", "application/json");

 // Request parameters and other properties.
    List<NameValuePair> urlParameters = new ArrayList<NameValuePair>(2);
    urlParameters.add(new BasicNameValuePair("UserId", "xxxxxx"));
    urlParameters.add(new BasicNameValuePair("Password", "xxxxxxx"));

    try {
       httppost.setEntity(new UrlEncodedFormEntity(urlParameters));

 //Execute and get the response.
       HttpResponse response = httpclient.execute(httppost);
       HttpEntity entity = response.getEntity();
       BufferedReader rd = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
       String line;
       while(null !=(line=rd.readLine())){

       System.out.println(line);
       }

   }

   catch (Exception e){

       e.printStackTrace();
   }
}

}

在上面的代码中，我正在对URL登录端点发出post请求。解析后我看到的响应是：

An error occurred, please try again or contact the administrator with this error id, 26225

我可以通过浏览器手动登录URL。不知道我在代码中出错了。

首先我的方法是否正确？我可以确定我的代码是对的吗？如果是，为什么响应是错误的呢？

任何帮助将不胜感激。谢谢。