Android Studio

private void selectAll(String name, String email,String password){

    Retrofit retrofit = new Retrofit.Builder()
            .baseUrl(Constants.BASE_URL)
            .addConverterFactory(GsonConverterFactory.create())
            .build();

    RequestInterface requestInterface = retrofit.create(RequestInterface.class);

    User user = new User();
    user.setName(name);
    user.setEmail(email);
    user.setPassword(password);
    ServerRequest request = new ServerRequest();
    request.setOperation(Constants.SELECT_ALL);
    request.setUser(user);
    Call<ServerResponse> response = requestInterface.operation(request);

    response.enqueue(new Callback<ServerResponse>() {
        @Override
        public void onResponse(Call<ServerResponse> call, retrofit2.Response<ServerResponse> response) {

            ServerResponse resp = response.body();
            Snackbar.make(getView(), resp.getMessage() + " 2222", Snackbar.LENGTH_LONG).show();     // getMessage() found in ServerRequest.java

        }

        @Override
        public void onFailure(Call<ServerResponse> call, Throwable t) {

            Log.d(Constants.TAG,"failed");
            Snackbar.make(getView(), t.getLocalizedMessage(), Snackbar.LENGTH_LONG).show();


        }
    });
}




       index.php

       if($operation == 'selectall'){

        if(isset($data -> user ) && !empty($data -> user) && isset($data -> user -> name)
            && isset($data -> user -> email) && isset($data -> user -> password)){

            $user = $data -> user;
            $name = $user -> name;
            $email = $user -> email;
            $password = $user -> password;

        echo $fun -> selectAll($name, $email, $password);


        } else {

            echo $fun -> getMsgInvalidParam();

        }

    }


Function.php

public function selectAll($name, $email, $password) {

$db = $this -> db;

if (!empty($name) && !empty($email) && !empty($password)) {

        $result = $db -> selectData($name, $email, $password);

        if ($result) {

            $response["message"] = $result;

            return json_encode($response);

        } else {

            $response["message"] = "failure";

            return json_encode($response);

        }
} else {

    return $this -> getMsgParamNotEmpty();

   }
 }


 DBConnect.php
 public function selectData($name,$email,$password){

$sql = 'SELECT * FROM users';

$query = $this -> conn -> prepare($sql);
$query -> execute(array(':email' => $email));
$data = $query -> fetchObject();

if ($query) {

    $user["name"] = $data -> name;
    $user["email"] = $data -> email;
    $user["unique_id"] = $data -> unique_id;

    return $user;

} else {

    return false;
}