public class Client {	public static void main(String[] args) throws UnknownHostException,			IOException {		System.out.println("-- client start. -- ");		String s = "";		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));		s = br.readLine();		while (!s.equals("bye")) {			Socket socket = new Socket("localhost", 8804);			DataOutputStream out = new DataOutputStream(socket.getOutputStream());			DataInputStream in = new DataInputStream(socket.getInputStream());						out.writeUTF(s);			System.out.println("Server: " + in.readUTF());			s = br.readLine();		}		System.out.println("-- client stop! --");	}}public class Server {	static int counter = 0;	public static void main(String[] args) throws IOException {		System.out.println("-- server start. --");		ServerSocket server = new ServerSocket(8804);		String a = "";		do {			Socket socket = server.accept();			DataInputStream in = new DataInputStream(socket.getInputStream());			DataOutputStream out = new DataOutputStream(					socket.getOutputStream());			a = in.readUTF();			System.out.println("Client: " + a);			out.writeUTF(a + " - " + counter++);		} while (!a.equals("bye"));		System.out.println("-- server stop. --");	}}