Datagram client : Runtime Exceptions

Question

Hi,
I have written a client side prog. When I run it I am getting following exception:
Exception in thread "main" java.lang.NullPointerException
at ReadClient.TheClient(ReadClient.java:11)
at ReadClient.main(ReadClient.java:16)
The code is given below:
import java.net.*;
class ReadClient{
public static int serverPort = 666;
public static int clientPort = 999;
public static int buffer_size=1024;
public static DatagramSocket ds;
public static byte buffer[ ] = new byte [buffer_size];
public static void TheClient ( ) throws Exception{
while (true) {
DatagramPacket p = new DatagramPacket(buffer, buffer.length);
ds.receive ( p);
System.out.println(new String( p.getData( ), 0, p.getLength ( )));
public static void main (String args[ ]) throws Exception{
TheClient( );
Can somebody plz. help me in this regard?
Zulfi

Answer 1

You have not created an instance of the DatagramSocket before you call receive so it is null.
You need a line like: ds=new DatagramSocket();