Sending message across network

[flag]

Using netbeans i'm trying to get a message from one computer to another. Below is my sender and reciever code, can anyone tell me if im on the right track. First is sender second is reciever, i'm also having problems with cannot find symbol.

Cheers

package javaapplication1;

public class Main
{

public static void main(String[] argv)
{
try
{
InetAddress addr = InetAddress.getLocalHost();
int sendPortNumber = 4000;
int portNumber = 3000;

Command data = new Command("BUY","forks",10); // data to send

byte[] buffer = data.toString().getBytes();

// assume that machine and port to send to are in arg vector
if (argv.length == 2)
{
try
{
addr = InetAddress.getByName(argv[0]);
portNumber = Integer.parseInt(argv[1]);
}
catch (UnknownHostException uh)
{
addr = InetAddress.getLocalHost();
}
}

// now create and send packet
DatagramPacket packet =
new DatagramPacket(buffer,buffer.length,addr,portNumber);

DatagramSocket socket = new DatagramSocket(sendPortNumber);

System.out.println("ready to send on " +
socket.getLocalAddress().toString() +
" port: " + socket.getLocalPort());
socket.send(packet);

System.out.println("Packet data sent");

}
catch (UnknownHostException uh)
{
System.out.println("ERROR: " + uh);
System.exit(0);
}
catch (IOException ioe)
{
System.out.println("ERROR: " + ioe);
}
}
}


public class ex10receiver
{
public static void main(String[] argv)
{
try
{
int portNumber = 3000;

byte[] buffer = new byte[1024];

// assume that machine and port to send to are in arg vector
if (argv.length == 1)
{
portNumber = Integer.parseInt(argv[1]);
}

// now create and send packet
DatagramPacket packet =
new DatagramPacket(buffer,buffer.length);

DatagramSocket socket = new DatagramSocket(portNumber);
socket.setSoTimeout(0);

System.out.println("ready to receive on " + socket.getLocalAddress().toString() + " port: " + socket.getLocalPort());

socket.receive(packet);

Command data = new Command(packet.getData());
System.out.println("Received " + data.toString());

}
catch (IOException ioe)
{
System.out.println("ERROR: " + ioe);
}
}
}