Thread: problem with a java client connecting to servlet

Hi all,
I am trying to create my first servlet with a basic client that sends some data to the servlet and gets a reply back.
I want to do that in order do go further where i want to develop an android app that communicates with a server. I actually did a small application that does prety much what i need, but i used sockets, and there is no way i can find to post that java socket server on the internet in order to connect with my android application. So from what i have read online, i figured that i need a servlet in order to have the ability to publish it online.
Most of the servlet examples i found were communicating with a web browser (something that i dont need) and i found this tutorial with a client sending a string to the server and gets a reply.
This is the servlet code from the tutorial:

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class HelloJavaWorld extends HttpServlet {
    private final static String _USERNAME = "username";
 
    protected void doPost( HttpServletRequest request, HttpServletResponse response )
        throws ServletException, IOException {
 
        PrintWriter out = response.getWriter();
        String username = request.getParameter( _USERNAME );
 
        response.setContentType("text/html");
        out.println("");
        out.println("");
            out.println("HelloWorld");
        out.println("Hello " + username + "!");
    } 
}

and this is the client

import java.io.*;
import java.net.*;
public class ContactServlet {
    public static void main( String [] args ) {
 
        try {            
            URL url = new URL(" http://127.0.0.1:8080/test/FileCounter");
            URLConnection conn = url.openConnection();
            conn.setDoOutput(true);
 
            BufferedWriter out = 
                new BufferedWriter( new OutputStreamWriter( conn.getOutputStream() ) );
            out.write("username=javaworld\r\n");
            out.flush();
            out.close();
            BufferedReader in = 
                new BufferedReader( new InputStreamReader( conn.getInputStream() ) );
 
            String response;
            while ( (response = in.readLine()) != null ) {
                System.out.println( response );
            }
            in.close();
        }
        catch ( MalformedURLException ex ) {
            // a real program would need to handle this exception
        }
        catch ( IOException ex ) {
System.out.println("ex.getMessage());
 
            // a real program would need to handle this exception
        }
    }
}

The thing is that i can not sent data from the client. The server is working OK, from a browser i get this

HTML Code:

HelloWorld Hello null!

since i dont sent anything to get a reply.
From the java client i get this exception

Server returned HTTP response code: 405 for URL: http://127.0.0.1:8080/test/FileCounter

If i delete all the commands that have to do with the transmision from the client, i.e.

  BufferedWriter out = 
                new BufferedWriter( new OutputStreamWriter( conn.getOutputStream() ) );
            out.write("username=javaworld\r\n");
            out.flush();
            out.close();

I am geting the same result as the web browser

HelloWorld
Hello null!

Does anyone have ANY idea why this is happening? I dont know much about servlets (as you might guessed) and a ready tutorial shouldn't give me this much trouble.
thanks in advance,
ilias

I dont get it!
request.getContentLength()
returns the actual length of the string transmitted, but there is no way to get the String, since
request.getAttribute(_USERNAME)
returns null!

So stupid of me!!
I have been working all this time on my 10' netbook, and didnt see that i changed one crusial line!
now that i sat on my proper desktop i saw the mistake in 2 mins!!!
Thanks alot.
Do you know if this is the best way to communicate between a server and an android client?
I have been trying to see what is the best protocol, but i just cant figure it out.
I should post a line on the android forum, i guess.

Thanks again