java Code for Simple Client-Server Communication

Client Side

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;

import java.net.UnknownHostException;
//this program just sent a message to the server through a socket("localhost",3009);

public class Clientsent {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
      
            Socket requestSocket;
            DataOutputStream out;
            DataInputStream in;
            String sent="how was the day";
        try{

            requestSocket = new Socket("localhost", 3009);
            System.out.println("Connected to the server ");
            out = new DataOutputStream(requestSocket.getOutputStream());//creating outputstream object (for writing data to a socket("local",3009) so that the server can read that data from the that socket)
          
            out.flush();
           
            out.writeUTF(sent) ;           //method that writes the message to the socket("localhost",3009);
             System.out.println(sent);
         
           in = new DataInputStream(requestSocket.getInputStream());  //creating inputstream object for reading data from socket from socket("localhost",3009).
           String getmessagefromserver= in.readUTF();// method that reads data from the socket....
           System.out.println("msg from server >>>>"+getmessagefromserver);
            out.flush();
            out.close();
            in.close();
            requestSocket.close();
                }
        catch(UnknownHostException unknownHost){
      
       
            System.err.println("You are trying to connect to an unknown host!");
       
        }
        catch(IOException ioException){
      
        }
     
       
    }
}

Server Side

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

    public static void main(String[] args) {
      ServerSocket providerSocket;
      Socket skt;
  
      DataOutputStream out;
       DataInputStream in;
       
     
            try{
               
            providerSocket = new ServerSocket(3009);
            System.out.println("Waiting for connection");

            System.out.println("Ready to Connect");
            skt= providerSocket.accept();//listens for any client requestand assign to a socket obj
          
            in = new DataInputStream(skt.getInputStream());
            System.out.println("error locating");
            String s;
            s=in.readUTF();
            System.out.println("error isolating");
          
            System.out.println("client >>"+s);
             out = new DataOutputStream(skt.getOutputStream());
          
            out.writeUTF("message accepted");
            out.flush();
            in.close();
            out.close();
            skt.close();
            }
       catch(Exception e){
      
       System.out.println("error"+e);
      
       }
      
     
   
    }
}