Java - Chat

// Server.java
package chat;

import java.io.*;
import java.util.*;
import java.net.*;
import static java.lang.System.out;

public class Server {

    ArrayList<String> users = new ArrayList<String>();
    ArrayList<HandleClient> clients = new ArrayList<HandleClient>();

    int PORT = 3333;
    int NumClients = 10;

    public Server() throws Exception {
        ServerSocket server = new ServerSocket(PORT, NumClients);
        out.println("Server Connected...");
        while (true) {
            Socket client = server.accept();
            HandleClient handleClient = new HandleClient(client);
            clients.add(handleClient);
        }  // end of while
    }

    public void boradcast(String user, String message) {
        // send message to all connected users
        for (HandleClient handleClient : clients) {  // clients.size() => number of clients
            if (!handleClient.getUserName().equals(user)) {
                handleClient.sendMessage(user, message);
            }
        }
    }

    public static void main(String[] args) throws Exception {
        new Server();
    } // end of main

    class HandleClient extends Thread {  // beginning of inner class

        String loginName = "";
        BufferedReader fromClients;
        PrintWriter toClients;

        public HandleClient(Socket client) throws Exception {
            // get fromClients and toClients streams
            fromClients = new BufferedReader(new InputStreamReader(client.getInputStream()));
            toClients = new PrintWriter(client.getOutputStream(), true);
            // read loginName
            toClients.println("Please Enter a User Name: ");
            loginName = fromClients.readLine();
            users.add(loginName); // add to ArrayList
            toClients.println("Welcome " + loginName);
            toClients.println("Write \"EXIT\" to exit, and write your login name for your identification.\nLet's talk");
            start();
        }

        public void sendMessage(String uname, String msg) {
            toClients.println(uname + ":" + msg);
        }

        public String getUserName() {
            return loginName;
        }

        public void run() {
            String messageFromClient;
            try {
                while (true) {
                    messageFromClient = fromClients.readLine();
                    if ("EXIT".equals(messageFromClient)) {
                        toClients.println("Closing Connection  . . . Goodbye");
                        clients.remove(this);
                        users.remove(loginName);
                        break;
                    } else if (loginName.equals(messageFromClient)) {
                        toClients.println("OK");
                    } else {
                        boradcast(loginName, messageFromClient);
                    }// method  of outer class - send messages to all
                }// end of while
            } // try
            catch (Exception e) {
                System.out.println(e.getMessage());
            }
        } // end of run()
    }
} // end of Server


// Client.java
package chat;

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

public class Client {

    String host = "localhost";
    int port = 3333;
    private Socket socket;
    private PrintWriter out;
    private Scanner scanner;
    private InputStreamReader in;

    public Client() throws IOException {
        socket = new Socket(host, port);
        in = new InputStreamReader(socket.getInputStream());
        scanner = new Scanner(in);
        out = new PrintWriter(socket.getOutputStream());

        new Thread(new Runnable() {
            @Override
            public void run() {
                String receivingMessage;
                try {
                    while (true) {
                        receivingMessage = scanner.nextLine();
                        System.out.println(receivingMessage);
                    }
                } catch (Exception e) {

                }
            }
        }).start();

        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    while (true) {
                        Scanner scn = new Scanner(System.in);
                        String input = scn.nextLine();
                        out.println(input);
                        out.flush();
                    }
                } catch (Exception e) {

                }
            }
        }).start();

    }

    public static void main(String[] args) throws IOException {
        new Client();
    }
}