Java™ Network Programming and Distributed Computing

5.6. User Datagram Protocol Example

To demonstrate how UDP packets are sent and received, we'll compile and run two small examples. The first will bind to a local port, read a packet, and display its contents and addressing information. The second example will send the packet read by the first.

Code for PacketReceiveDemo

 import java.net.*; import java.io.*; // Chapter 5, Listing 1 public class PacketReceiveDemo { public static void main (String args[]) { try { System.out.println ("Binding to local port 2000"); // Create a datagram socket, bound to the // specific port 2000 DatagramSocket socket = new DatagramSocket(2000); System.out.println ("Bound to local port " + socket.getLocalPort()); // Create a datagram packet, containing a // maximum ...