Question

look this code is a correct but i want modify it to allow the client to have three attempts to login to the server

package hw2;

import java.net.*;
import java.util.Formatter;
import java.util.Random;
import java.util.Scanner;
import java.io.*;

public class Client {
   Socket server;
   int port;
   Formatter toNet = null;
   Scanner fromNet = null;
   Scanner fromUser = new Scanner(System.in);

   public Client() {
       try {
           // login at server at local host port 4000
           server = new Socket("localhost",4000);
           System.out.println("UserName: ");
           String user = fromUser.nextLine();
           System.out.println("Password: ");
           String pass = fromUser.nextLine();
           //to dedecate with the server
           fromNet = new Scanner(server.getInputStream());
           toNet = new Formatter(server.getOutputStream());
           toNet.format("%s\n", user);
           toNet.flush();
           toNet.format("%s\n", pass);
           toNet.flush();
           String response=fromNet.nextLine();
           if(!response.equals("valid") {
               System.out.println("Invalid Login!!");
           }else {
               // if login is successful vote at local host port 4001
               server = new Socket("localhost",4001);//establish new connection
               //establish a strem
               toNet = new Formatter(server.getOutputStream());
               System.out.prinln("Enter your vote 0-9: ");
                   String vote = formUser.nextLine();
                   toNet.format("%s\n", vote);
                   toNet.flush();
           }
              
       } catch (IOException ioe) { }
   }

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

package hw2;
import java.net.*;
import java.io.*;

public class Server extends Thread{//multiple services each is a thread on different port
   ServerSocket server;
   Socket client;
   int port;
  
  
   public Server(int port) {
       this.port=port;
       server= new ServerSocket (port);
       run();
   }
   public void run() {
       try {
           while(true) {
               server = new ServerSocket(port);
               client = server.accept();
               switch(port) {
               case 4000:
                   new ServiceServer0(client).start();
                   break;
               case 4001:           
                   new ServiceServer1(client).start();
                   break;
               default:
                   System.out.println("Invalid port");
                   System.exit(0);
                  
               }
           }
       }catch(IOException ioe) {}
   }

   public static void main(String[] args) {
       new Server (4000).start();
       new Server(4001).start();
      
   }

}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer0 extends Thread{//login multithreaded service
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;
   private String login[][] = { { "user1", "pass1" }, { "user2", "pass2" }, { "user3", "pass3" }, { "user4", "pass4" },
           { "user5", "pass5" }, { "user6", "pass6" }, { "user7", "pass7" }, { "user8", "pass8" },
           { "user9", "pass9" }, };
   public ServiceServer0(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("Login Service: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());
           String user = fromNet.nextLine(); //read the user
           String pass = fromNet.nextLine(); // read the pass
           String respone = " ";
           boolena fount = false;
           for (int i=0; i<long.length; i++) {
               if(login[i][0].equals(user) && login[i][1].equals(pass)) {
                   respone="valid";
                   found = true;
                   break; // to go out from for loop
               }
           }
          
           if(!found)
               response= "Invalid";
              
           toNet.format("%s\n", response);
           toNet.flush();
          
       }catch(IOException ioe) {}  
   }
}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer1 extends Thread{
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;
   static int[]votes = new int[10];//one instance to accumulate voting results
   public ServiceServer1(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("Voting Service: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());
           int vote = Integer.parseInt(fromNet.nextLine());
           ++votes[vote];
          
           showVotes();
       }catch(IOException ioe) { }
   }
   void showVotes() {
      
   }
}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer2 extends Thread{//other services in similar manner
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;

   public ServiceServer2(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("ServiceServer2: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());

          
       }catch(IOException ioe) {}
      
   }

}

Answer 1

package hw2;

import java.net.*;

import java.util.Formatter;

import java.util.Random;

import java.util.Scanner;

import java.io.*;

public class Client {

   Socket server;

   int port;

   Formatter toNet = null;

   Scanner fromNet = null;

   Scanner fromUser = new Scanner(System.in);

   public Client() {

       try {

           // login at server at local host port 4000

           server = new Socket("localhost",4000);

           //to dedecate with the server

           fromNet = new Scanner(server.getInputStream());

           toNet = new Formatter(server.getOutputStream());

           for(int i=0;i<3;i++){

           System.out.println("UserName: ");

           String user = fromUser.nextLine();

           System.out.println("Password: ");

           String pass = fromUser.nextLine();

         

          

           toNet.format("%s\n", user);

           toNet.flush();

           toNet.format("%s\n", pass);

           toNet.flush();

           String response=fromNet.nextLine();

           if(!response.equals("valid")) {

               System.out.println("Invalid Login!!");

           }else {

               // if login is successful vote at local host port 4001

               server = new Socket("localhost",4001);//establish new connection

               //establish a strem

               toNet = new Formatter(server.getOutputStream());

               System.out.println("Enter your vote 0-9: ");

                   String vote = fromUser.nextLine();

                   toNet.format("%s\n", vote);

                   toNet.flush();

           }

           }

             

       } catch (IOException ioe) { }

   }

   public static void main(String[] args) {

           new Client();

   }

}

package hw2;
import java.net.*;
import java.io.*;

public class Server extends Thread{//multiple services each is a thread on different port
   ServerSocket server;
   Socket client;
   int port;
  
  
   public Server(int port) {
       this.port=port;
       server= new ServerSocket (port);
       run();
   }
   public void run() {
       try {
           while(true) {
               server = new ServerSocket(port);
               client = server.accept();
               switch(port) {
               case 4000:
                   new ServiceServer0(client).start();
                   break;
               case 4001:           
                   new ServiceServer1(client).start();
                   break;
               default:
                   System.out.println("Invalid port");
                   System.exit(0);
                  
               }
           }
       }catch(IOException ioe) {}
   }

   public static void main(String[] args) {
       new Server (4000).start();
       new Server(4001).start();
      
   }

}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer0 extends Thread{//login multithreaded service
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;
   private String login[][] = { { "user1", "pass1" }, { "user2", "pass2" }, { "user3", "pass3" }, { "user4", "pass4" },
           { "user5", "pass5" }, { "user6", "pass6" }, { "user7", "pass7" }, { "user8", "pass8" },
           { "user9", "pass9" }, };
   public ServiceServer0(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("Login Service: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());
           String user = fromNet.nextLine(); //read the user
           String pass = fromNet.nextLine(); // read the pass
           String respone = " ";
           boolena fount = false;
           for (int i=0; i<long.length; i++) {
               if(login[i][0].equals(user) && login[i][1].equals(pass)) {
                   respone="valid";
                   found = true;
                   break; // to go out from for loop
               }
           }
          
           if(!found)
               response= "Invalid";
              
           toNet.format("%s\n", response);
           toNet.flush();
          
       }catch(IOException ioe) {}  
   }
}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer1 extends Thread{
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;
   static int[]votes = new int[10];//one instance to accumulate voting results
   public ServiceServer1(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("Voting Service: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());
           int vote = Integer.parseInt(fromNet.nextLine());
           ++votes[vote];
          
           showVotes();
       }catch(IOException ioe) { }
   }
   void showVotes() {
      
   }
}

package hw2;
import java.net.*;
import java.util.Formatter;
import java.util.Scanner;
import java.io.*;

public class ServiceServer2 extends Thread{//other services in similar manner
   Socket client;
   Scanner fromNet = null;
   Formatter toNet = null;

   public ServiceServer2(Socket client) {
       this.client = client;
   }
   public void run() {
       System.out.println("ServiceServer2: Serving client ...");
       try {
           fromNet = new Scanner(client.getInputStream());
           toNet = new Formatter(client.getOutputStream());

          
       }catch(IOException ioe) {}
      
   }

}