使用HttpUtility的Java Post请求

I am trying to send POST request to a web server using Java for this I have used HttpUtility Class reference here http://www.codejava.net/java-se/networking/an-http-utility-class-to-send-getpost-request

my code looks like this

package gehu_connect;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
class Downloader extends Thread
{

    private int username;
    private int password;
    @Override
    public void run(){
        Map<String, String> params = new HashMap<String, String>();
        String requestURL = "http://127.0.0.1/response_true";
        params.put("username", "16441027");
        params.put("Password", "myinternet");

        try {
            HttpUtility.sendPostRequest(requestURL, params);
            String[] response = HttpUtility.readMultipleLinesRespone();
            for (String line : response) {
                System.out.println(line);
            }
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        HttpUtility.disconnect();
    }

    void setUserId(int i) {
        this.username = i;
    }

    void setPassword(int i) {
       this.password = i;
    }
}

the problem is when I am Echoing out the $_POST array back as response I am getting empty array that means request was sent but without paremeters how can i resolve this problem its been a day googling .

I have already tried changing server also tried local and online server

the server runs php and code looks like this

<?php 
print_r($_POST);
print_r($_GET);
print_r($_REQUEST);
?>

and here is the output

Array
(
)
Array
(
)
Array
(
)