proksi tcp

public class ProxyServer extends Thread {

    private ServerSocket serverSocket;
    private final int serverPort=10100;
    private Map<String,Integer> map;

    public ProxyServer() {

        try {
            serverSocket=new ServerSocket(serverPort);
            map=new HashMap<>();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void run() {

        System.out.println("Server is running...");
        while (true){

            try {

                Socket socket=serverSocket.accept();
                new Thread(new ServerWorker(socket,map)).start();

            } catch (IOException e) {
                e.printStackTrace();
            }

        }

    }

    public static void main(String[] args) {
        ProxyServer proxyServer=new ProxyServer();
        proxyServer.start();
    }
}
-----------------SERVER-WORKER----------------------
public class ServerWorker extends Thread {

    private Socket socket;
    private PrintWriter printWriter;
    private Scanner scanner;
    private Map<String,Integer> map;

    public ServerWorker(Socket socket, Map<String, Integer> map) {
        this.socket = socket;
        this.map = map;
        try {
            printWriter=new PrintWriter(socket.getOutputStream(),true);
            scanner=new Scanner(socket.getInputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void run() {

        if(scanner.hasNextLine()){
            String clientOrServer=scanner.nextLine();

            if(clientOrServer.equals("*server")){

                System.out.println("Server accepted...");
                if(scanner.hasNextLine()){
                    String urlPort=scanner.nextLine();
                    String[] parts=urlPort.split(":");
                    if(!map.containsKey(parts[0])){
                        map.put(parts[0],Integer.parseInt(parts[1]));
                        System.out.println(urlPort+" is added to map");
                        printWriter.println("You are successfully added to proxy");
                    }else {
                        printWriter.println("url already exists!!!");
                    }
                }

            }else if(clientOrServer.equals("*client")) {
                System.out.println("Client accepted...");

                while (true){
                    //send msg to client
                    printWriter.println("Enter url:");

                    //receive url
                    if(scanner.hasNextLine()){
                        String url=scanner.nextLine();

                        if(map.containsKey(url)){

                            int port=map.get(url);
                            printWriter.println(port);

                        }else {
                            printWriter.println("url does not exists...");
                        }
                    }
                }

            }else {
                System.out.println("Something else..");
            }

        }

    }
}
---------------FINKI-SERVER-------------------
public class FinkiServer extends Thread {

    private String url="finki.com.mk";
    private ServerSocket serverSocket;
    private final int serverPort=10940,proxyPort=10100;
    private PrintWriter printWriter;
    private Socket socket;
    private Scanner scanner;

    public FinkiServer() {
        try {

            serverSocket=new ServerSocket(serverPort);
            socket=new Socket("127.0.0.1",proxyPort);
            printWriter=new PrintWriter(socket.getOutputStream(),true);
            scanner=new Scanner(socket.getInputStream());

        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void run() {

        //send server data to proxy server
        printWriter.println("*server");
        printWriter.println(url+":"+serverPort);

        //get message from server
        if(scanner.hasNextLine()){
            System.out.println(scanner.nextLine());
        }

        while (true){
            try {
                Socket socket1=serverSocket.accept();
                System.out.println("Client search for your url.");
                printWriter=new PrintWriter(socket1.getOutputStream(),true);
                printWriter.println("This is server of FINKI.");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }

    public static void main(String[] args) {
        FinkiServer finkiServer=new FinkiServer();
        finkiServer.start();
    }
}
-----------------CLIENT--------------------------
public class Client extends Thread {

    private Socket socket;
    private final int proxyPort=10100;
    private PrintWriter printWriter;
    private BufferedReader reader;
    private Scanner scanner;

    public Client() {

        try {
            socket=new Socket("127.0.0.1",proxyPort);
            printWriter=new PrintWriter(socket.getOutputStream(),true);
            reader=new BufferedReader(new InputStreamReader(System.in));
            scanner=new Scanner(socket.getInputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void run() {

        //new Thread(new ClientListener(socket)).start(); //start listening

        try {

            printWriter.println("*client");

            while (true){
                //send url to proxy
                if(scanner.hasNextLine()){
                    String msg=scanner.nextLine();
                    System.out.println(msg);
                    String url=reader.readLine();
                    printWriter.println(url);
                }

                //receive port of chosen url from proxy
                if(scanner.hasNextLine()){
                    String port=scanner.nextLine();
                    if(port.equals("url does not exists...")){
                        System.out.println(port);
                    }else {
                        int portInt=Integer.parseInt(port);
                        Socket socket1=new Socket("127.0.0.1",portInt);
                        Scanner readDataFromChosenServer=new Scanner(socket1.getInputStream());
                        if(readDataFromChosenServer.hasNextLine()){
                            System.out.println(readDataFromChosenServer.nextLine());
                        }
                    }

                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static void main(String[] args) {
        Client client=new Client();
        client.start();
    }
}
----------------CLIENT-LISTENER--------------
public class Client extends Thread {

    private Socket socket;
    private final int proxyPort=10100;
    private PrintWriter printWriter;
    private BufferedReader reader;
    private Scanner scanner;

    public Client() {

        try {
            socket=new Socket("127.0.0.1",proxyPort);
            printWriter=new PrintWriter(socket.getOutputStream(),true);
            reader=new BufferedReader(new InputStreamReader(System.in));
            scanner=new Scanner(socket.getInputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void run() {

        //new Thread(new ClientListener(socket)).start(); //start listening

        try {

            printWriter.println("*client");

            while (true){
                //send url to proxy
                if(scanner.hasNextLine()){
                    String msg=scanner.nextLine();
                    System.out.println(msg);
                    String url=reader.readLine();
                    printWriter.println(url);
                }

                //receive port of chosen url from proxy
                if(scanner.hasNextLine()){
                    String port=scanner.nextLine();
                    if(port.equals("url does not exists...")){
                        System.out.println(port);
                    }else {
                        int portInt=Integer.parseInt(port);
                        Socket socket1=new Socket("127.0.0.1",portInt);
                        Scanner readDataFromChosenServer=new Scanner(socket1.getInputStream());
                        if(readDataFromChosenServer.hasNextLine()){
                            System.out.println(readDataFromChosenServer.nextLine());
                        }
                    }

                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    public static void main(String[] args) {
        Client client=new Client();
        client.start();
    }
}