Communicate 2 android in 2 emulator

[Jason Gosling]

Hi, I have a project related to socket programming

First of all, here is my connection between client-server using UDP Socket, result can be viewed on Log Cat

//Activity: UDPConnection
package org.anddev.android.udpconnection;

import android.app.Activity;
import android.os.Bundle;

public class UDPConnection extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        new Thread(new Server()).start();
        /* GIve the Server some time for startup */
        try {
               Thread.sleep(500);
          } catch (InterruptedException e) { }
          
        // Kickoff the Client
        new Thread(new Client()).start(); 
    }
}    

//Client
package org.anddev.android.udpconnection;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import android.util.Log;

public class Client implements Runnable {

	@Override
	public void run() {
		// TODO Auto-generated method stub
		try {
            // Retrieve the ServerName
            InetAddress serverAddr = InetAddress.getByName(Server.SERVERIP);
            
            Log.d("UDP", "C: Connecting...");
            /* Create new UDP-Socket */
            DatagramSocket socket = new DatagramSocket();
            
            /* Prepare some data to be sent. */
            byte[] buf = ("Hello from Client").getBytes();
            
            /* Create UDP-packet with
             * data & destination(url+port) */
            DatagramPacket packet = new DatagramPacket(buf, buf.length, serverAddr, Server.SERVERPORT);
            Log.d("UDP", "C: Sending: '" + new String(buf) + "'");
            
            /* Send out the packet */
            socket.send(packet);
            Log.d("UDP", "C: Sent.");
            Log.d("UDP", "C: Done.");
            
            socket.receive(packet);
            Log.d("UDP", "C: Received: '" + new String(packet.getData()) + "'");

       } catch (Exception e) {
            Log.e("UDP", "C: Error", e);
       } 
	}

}
    

//Server
package org.anddev.android.udpconnection;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import android.util.Log;

public class Server implements Runnable {
	
	public static final String SERVERIP = "127.0.0.1"; // 'Within' the emulator!
    public static final int SERVERPORT = 4444; 
    
	@Override
	public void run() {
		// TODO Auto-generated method stub
		try {
            /* Retrieve the ServerName */
            InetAddress serverAddr = InetAddress.getByName(SERVERIP);

            Log.d("UDP", "S: Connecting...");
            /* Create new UDP-Socket */
            DatagramSocket socket = new DatagramSocket(SERVERPORT, serverAddr);

            /* By magic we know, how much data will be waiting for us */
            byte[] buf = new byte[17];
            /* Prepare a UDP-Packet that can
             * contain the data we want to receive */
            DatagramPacket packet = new DatagramPacket(buf, buf.length);
            Log.d("UDP", "S: Receiving...");

            /* Receive the UDP-Packet */
            socket.receive(packet);
            
            Log.d("UDP", "S: Received: '" + new String(packet.getData()) + "'");
            Log.d("UDP", "S: Done.");
            
            InetAddress clientAddr = packet.getAddress();
            int clientPort = packet.getPort();
            String s = "Thanks";
            buf = s.getBytes();
            packet = new DatagramPacket(buf, buf.length, clientAddr, clientPort);
            
            Log.d("UDP", "S: Sending: '" + new String(buf) + "'");
            socket.send(packet);

       } catch (Exception e) {
            Log.e("UDP", "S: Error", e);
       } 
	}

}
 

It can be done, I'm sure

But my problems are

[*]I couldn't use TCP Socket even though it's said that it can be done with TCP, in theory
[*]I couldn't run my example onto 2 emulators, server and client, each onto one emulator

=======>>>>>> I really need help. Please