Client

package chat.client;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.net.InetAddress;
import java.net.Socket;
import java.util.Scanner;

public class Client {

    private Socket socket;
    private DataInputStream input;
    private DataOutputStream output;

    public Client() throws Exception {

        socket = new Socket(InetAddress.getLocalHost(), 4444);
        System.out.println("Client started!");

        input = new DataInputStream(socket.getInputStream());
        output = new DataOutputStream(socket.getOutputStream());
        Scanner scanner = new Scanner(System.in);

        while (true) {

            String message = scanner.nextLine();
            output.writeUTF(message);

            message = input.readUTF();
            System.out.println(message);
        }
    }

    public static void main(String[] args) {
        try {
            new Client();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}