安卓制作服务器请求

我目前正在Android下制作一个应用程序，使我能够连接用户。我使用常规的安卓服务器请求。我调用存储在我的服务器上的 php 文件，该文件查看输入的用户当前是否在 BDD 中注册，但它根本不起作用......

这是我的 php 文件：

<?php
$con = mysqli_connect("localhost", "user", "userpass", "Android");
$username = $_POST["username"];
$password = $_POST["password"]
$statement = mysqli_prepare($con, "SELECT * FROM Utilisateur where username = ? AND password = ?");

mysqli_stmt_bind_param($statement, "ss", $username, $password); 
mysqli_stmt_execute($statement);
mysqli_stmt_store_result($statement);
mysqli_stmt_bind_result($statement, $userID, $name, $username, $mail, $password, $adresse, $ville, $zipCode);
$user = array();
while(mysqli_stmt_fetch($statement)){
  $user[name] = $name;
  $user[username] = $username;
  $user[mail] = $mail;
  $user[password] = $password;
  $user[adresse] = $adresse;
  $user[ville] = $ville;
  $user[zipCode] = $zipCode;
}
echo json_encode($user);
mysqli_stmt_close($statement);
mysqli_close($con);
 ?>

这是我在 Java 中的请求（有一个 user：password，因为您需要进行身份验证才能访问我服务器上的任何网页）

public static final int CONNECTION_TIMEOUT = 1000 * 15;
public static final String SERVER_ADDRESS = "http://user:userpassword@62.210.193.223/Android/";
public class fetchUserDataAsyncTask extends AsyncTask<Void, Void, User> {
        User user;
        GetUserCallBack userCallBack;
        public fetchUserDataAsyncTask(User user, GetUserCallBack callBack) {
            this.user = user;
            this.userCallBack = callBack;
        }

        @Override
        protected User doInBackground(Void... params) {
            User returnedUser;
            try {
                URL url = new URL(SERVER_ADDRESS + "FetchUserData.php");
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("POST");
                Uri.Builder builder = new Uri.Builder().appendQueryParameter("username", user.username)
                        .appendQueryParameter("password", user.password);
                String query = builder.build().getEncodedQuery();
                OutputStream os = conn.getOutputStream();
                BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
                writer.write(query);
                writer.flush();
                writer.close();
                os.close();
                conn.connect();
                InputStream in = new BufferedInputStream(conn.getInputStream());
                String response = IOUtils.toString(in, "UTF-8");
                JSONObject jResponse = new JSONObject(response);
                if (jResponse.length() == 0) {
                    returnedUser = null;
                } else {
                    String name = jResponse.getString("name");
                    String mail = jResponse.getString("mail");
                    String adresse = jResponse.getString("adresse");
                    String ville = jResponse.getString("ville");
                    int zipCode = jResponse.getInt("zipCode");
                    returnedUser = new User(name, user.name, user.password, mail, adresse, ville, zipCode);

                }
                return returnedUser;

            } catch (IOException | JSONException e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(User returnedUser) {
            progressDialog.dismiss();
            userCallBack.done(returnedUser);
            super.onPostExecute(returnedUser);
        }
    }

我在调试模式下启动了我的应用程序，并捕获了此异常：

java.io.FileNotFoundException: http://user:userpassword@62.210.193.223/Android/FetchUserData.php

我什至尝试在我的网络浏览器中对 url 进行 C/C 并执行该文件。当然，它返回了[]，因为我没有在呼叫中包含POST。

完全迷失了，因为 android 对我来说很新，我真的不知道去哪里寻找解决这个问题的方法......如果有人能帮助我解决这个问题，将不胜感激:)

干杯星体