How to go to a website using variables then read whats on the website?

I am trying to make a simple authentication program, in which (I want) my program to go to a url using variables then read what my website says and if its true then do something
EX: mywebsite.com?authentication=variable1

Then my website will echo either 'YES' or 'NO' depending on if variable1 equals what I want it the equal.
PHP Example Code:

Code:

---

<?php
       
        $auth = $_GET['authentication'];
        if($auth == '123' || $auth == '234'){
                echo 'YES';
        }
        else{
                echo 'NO';
        }
       
?>

---

Look at using the HTTPURLConnection class for the client.
Do you have an existing website/server?

Not existing, im away from my desktop, but I can get one easily and implement my code into it.

Is that it? No further questions?

No, I found this:
http://www.java-forums.org/java-tips...a-program.html