Socket_programming(UDP)

UDP
------------------Client-------------------------
import java.io.*;
import java.net.*;
public class client{
    public static void main(String[] args) throws IOException{
        DatagramSocket client = new DatagramSocket();
        InetAddress add = InetAddress.getByName("localhost");
        String msg = "Hello Server";
        byte[] buf = msg.getBytes();
        DatagramPacket packet = new DatagramPacket(buf, buf.length,add,1234);
        client.send(packet);
        client.close();

    }
}
---------------------Server-------------------------
import java.io.*;
import java.net.*;
public class server {
    public static void main(String[] args) throws IOException{
        DatagramSocket server = new DatagramSocket(1234);
        byte[] buf = new byte[256];
        DatagramPacket packet = new DatagramPacket(buf,buf.length);
        server.receive(packet);
        String response = new String(packet.getData());
        System.out.println("Response Data :: "+response);
        server.close();
    }

}
---------------------------------------------------------------------------
TCP
------------------Client-------------------------
import java.io.*;
import java.net.*;
import java.util.Scanner;
public class client{
    public static void main(String[] args) {
        try{
            Scanner sc = new Scanner(System.in);
            Socket s=new Socket("localhost",6666);
            DataOutputStream dout=new DataOutputStream(s.getOutputStream());
            System.out.println("Establishing Connection...");
            System.out.println("Connection Established");
            System.out.println("Enter the message to be sent:");
            String str = sc.nextLine();
            dout.writeUTF(str);
            dout.flush();
            dout.close();
            System.out.println("Connection Closed");
            s.close();
            sc.close();
        }catch(Exception e){System.out.println(e);}
    }
}
-----------------------------Server-------------------
import java.io.*;
import java.net.*;
public class server {
    public static void main(String[] args) throws Exception {
        try{
            ServerSocket ss=new ServerSocket(6666);
            Socket s=ss.accept();//establishes connection
            DataInputStream dis=new DataInputStream(s.getInputStream());
            String  str=(String)dis.readUTF();
            System.out.println("message: "+str);
            System.out.println("Connection Closed");
            ss.close();
        }catch(Exception e){System.out.println(e);}
    }
}