Client-Server-Data-datagram socket UDP protocol

Using UDP protocol to send and receive text.
Client :
java code

import java.io.*;
import java.net.*;
import java.util.*;

public class TextClient {
    public static void main(String[] args) throws IOException {
         String ipAdress="112.43.54.1";
		 String hostName="HostNameHere";
       

	// get a datagram socket
        DatagramSocket socket = new DatagramSocket();

	// send request
	byte[] buf = new byte[256];
	InetAddress address = InetAddress.getByName(hostName);
	DatagramPacket packet = new DatagramPacket(buf, buf.length, address, 4445);
	socket.send(packet);

	// get response
	packet = new DatagramPacket(buf, buf.length);
	socket.receive(packet);

	// display response
	String received = new String(packet.getData(), 0);
	System.out.println("Text of the Moment: " + received);

	socket.close();
    }
}

Server :
java code

public class TextServer {
    public static void main(String[] args) throws java.io.IOException {
        new TextServerThread().start();
    }
}

java code

import java.io.*;
import java.net.*;
import java.util.*;

public class TextServerThread extends Thread {
    private DatagramserverSocket serverSocket = null;
    private DataInputStream in = null;
    private boolean moreTexts = true;

    public TextServerThread() throws IOException {
        super("TextServerThread");
        serverSocket = new DatagramserverSocket(4445);
	try {
	  // Read from file
            in = new DataInputStream(new FileInputStream("data.txt"));
	} catch (FileNotFoundException e) {
            System.err.println("Could not open Text file. Serving time instead.");
        }
    }

    public void run() {

        while (moreTexts) {
            try {
                byte[] buf = new byte[256];

                    // receive request
                DatagramPacket packet = new DatagramPacket(buf, buf.length);
                serverSocket.receive(packet);

		    // figure out response
                String dString = null;
                if (in == null)
                    dString = new Date().toString();
                else
                    dString = getMoreData();
                dString.getBytes(0, dString.length(), buf, 0);

                    // send the response to the client at "address" and "port"
                InetAddress address = packet.getAddress();
                int port = packet.getPort();
                packet = new DatagramPacket(buf, buf.length, address, port);
                serverSocket.send(packet);
            } catch (IOException e) {
                e.printStackTrace();
		moreTexts = false;
            }
        }
	serverSocket.close();
    }

    private String getMoreData() {
        String returnValue = null;
        try {
            if ((returnValue = in.readLine()) == null) {
                in.close();
		moreTexts = false;
                returnValue = "No more Data. ";
            }
        } catch (IOException e) {
            returnValue = "IOException occurred in server.";
        }
        return returnValue;
    }

}