Java typ Client

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

class dod extends Thread
{
    private ServerSocket serverSocket;
    private List<client> clientList;

    public dod(int port) throws IOException
    {
        serverSocket = new ServerSocket(port);
        clientList = new ArrayList<>();
    }
    @Override
    public void run()
    {
        while(true)
        {
            try
            {
                Socket clientSocket = serverSocket.accept();
                int id = clientList.size(); //generujesz jakieś id
                Client newClient = new Client(id, clientSocket);
                clientList.add(newClient);
                newClient.start();
            }
            catch (IOException e)
            {
                e.printStackTrace();
            }
        }
    }


    public static void main(String[] args) throws IOException
    {
        dod server = new Server(9999);
        server.start();
    }

Error:(10, 18) java: cannot find symbol
  symbol:   class client
  location: class dod

Error:(26, 17) java: cannot find symbol
  symbol:   class Client
  location: class dod

Error:(26, 40) java: cannot find symbol
  symbol:   class Client
  location: class dod

Error:(40, 26) java: cannot find symbol
  symbol:   class Server
  location: class dod

to
private List<client> clientList;

powinno wyglądać tak:
private List<Client> clientList;

private List<client> clientList = new ArrayList<>();

public class Client extends Thread{
private int id;
private Socket socket;
private OutputStream outputStream;
private InputStream inputStream;

public Client(int id, Socket socket){
    this.id = id;
    this.socket = socket;
}

@Override
public void run(){
    try {
        outputStream = socket.getOutputStream();
        inputStream = socket.getInputStream();
        String greetingMessage = "Hello I'm new client with id: " + id;
        outputStream.write(greetingMessage.getBytes());
    } catch (IOException e) {
        e.printStackTrace();
    }
}
}