Odtnhj

I need to implement a program to transfer files. I decided to make it using a chat template I've made about 1 month ago so I would have a chat with file transfer option.
The transfer should follow the following points:

1- Server only keeps a list of all files provided by connected clients (No file are actually located in the server, only their names)

2- Client "1" requests file "A" then:

if file "A" is located ONLY in client "2", then client "2" should send 100% of the file to client "1"

if file "A" is located in client "2" and client "3" also has file "A", then client "2" should send 50% of the file to client "1" and client "3" should send the other 50%.

(if the file is located in 4 clients i should be 25% each....and so it goes...)

I've already managed to make the server find out wich client is requesting the file and wich clients have it. But now I'm stuck, I don't know how to make the transfer.

Could someone give me an exemple of how to do it? or point me through the right direction?

[I'm aware my code has some flaws and I will fix it later, right now I need to make the transfer happen before working on fixes, so please, unless it's related, try to focus on that]

Server:

package tor;

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

public class Server extends Thread 

private String cname;
private Socket client;
public static Vector<PrintStream> clients;
public static Vector<String> clientnames;
public static Vector<String> archives;
public Server(Socket client) 
 this.client = client;



public static void main(String args) 
 clients = new Vector<PrintStream>();
 clientnames = new Vector<String>();
 archives = new Vector<String>();

 try 

 ServerSocket server = new ServerSocket(2391);
 System.out.println("Server Started!!n");
 while (true) 
 Socket client = server.accept();
 Server s = new Server(client);
 s.start();
 

 catch (IOException e) 
 System.out.println("Server could not start ");

 




@Override
public void run() 

 try 
 BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
 PrintStream out = new PrintStream(client.getOutputStream());
 cname = in.readLine();
 System.out.println(cname + " Connected --- SERVER!");

 if (cname == null) 
 System.out.println("Unknown Name");
 return;
 
 clientnames.add(cname);
 clients.add(out);
 connected(" ********** [", cname, "] Connected! **********");

 String arq;
 int size = in.read();
 System.out.println(size);
 for (int i = 0; i < size; i++) 
 arq = in.readLine();
 archives.add(arq);
 
 String msg = in.readLine();
 String selected;
 while (true) 
 while (!(msg).equals("/exit") && !(msg).equals("/Exit") && !(msg).equals("/EXIT")) (msg.equals("/Get")))
 msg = in.readLine();
 int gnum = Integer.parseInt(msg);
 selected=archives.get(gnum);
 returnAll("[", out, "]: ", "idreq");
 out.println("1");
 reqAll(selected);

 // I BELIVE HERE IS THE RIGHT PLACE TO MAKE DE TRANSFER CODE


 msg = in.readLine();
 else 
 returnAll("[", out, "]: ", msg);
 msg = in.readLine();
 
 
 msg = in.readLine();
 size = Integer.parseInt(msg);
 for (int i = 0; i <= size; i++) 
 arq = in.readLine();
 for(int j=0;j<archives.size();j++) 
 if (archives.get(j).equals(arq)) 
 archives.remove(j);
 
 
 
 returnAll(" ********** [", out, "] disconnected ", " ********** ");
 clients.remove(out);
 clientnames.remove(cname);
 client.close();
 break;
 
 catch (IOException e) 
 System.out.println("A Client disconnected ");
 



// METHOD TO SEND CONNECTION MESSAGE
public void connected(String msg1, String cname, String msg2) throws IOException 
 Enumeration<PrintStream> e = clients.elements();
 while (e.hasMoreElements()) 
 PrintStream message = (PrintStream) e.nextElement();
 message.println(msg1 + cname + msg2);
 


// METHOD TO RETURN MESSAGE TO ALL CLIENTS
public void returnAll(String msg1, PrintStream saida, String ac, String msg2) throws IOException 
 Enumeration<PrintStream> e = clients.elements();
 while (e.hasMoreElements()) 
 PrintStream message = (PrintStream) e.nextElement();
 message.println(msg1 + cname + ac + msg2);
 


public void reqAll(String req) throws IOException 
 Enumeration<PrintStream> e = clients.elements();
 while (e.hasMoreElements()) 
 PrintStream message = (PrintStream) e.nextElement();
 message.println(req);
 

Client:

package tor;

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


public class Client extends Thread 
 private Socket con;
 private static boolean done = false;
 static ArrayList<String> localArq = new ArrayList<String>();
 static int c=0;

public Client(Socket s) 
 con = s;


public static void main(String args) 


 try 
 String ip;
 Scanner s = new Scanner(System.in);
 System.out.print("Enter Server's IP: ");
 ip =s.next();
 Socket con = new Socket(ip, 2391);
 PrintStream out = new PrintStream(con.getOutputStream());
 System.out.println("Connected to Server!");
 System.out.print("Enter your Nickname: ");
 BufferedReader scan = new BufferedReader(new InputStreamReader(System.in));
 String cname = scan.readLine();
 out.println(cname);
 String dir="C:\javator\"+cname;
 Thread t = new Client(con);
 t.start();

 File folder = new File(dir);
 folder.mkdir();
 File listOfFiles = folder.listFiles();
 for (int i = 0; i < listOfFiles.length; i++) 
 if (listOfFiles[i].isFile()) 
 localArq.add(listOfFiles[i].getName());
 
 
 int size=localArq.size();
 out.write(size);
 for(int i=0;i<size;i++) 
 out.println(localArq.get(i));
 


 String msg;
 while (true) (msg.equals("/GET")) 
 catch (UnknownHostException e) 
 System.out.println(e.getMessage());
 catch (IOException e) 
 System.err.println(e.getMessage());
 


@Override
public void run() 
 try 
 BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
 String rmsg;
 String req;

 while (true) 
 rmsg = in.readLine();
 if (rmsg == null) 
 System.out.println("Connection Terminated");
 break;
 else if(rmsg.substring(rmsg.length() - 5).equals("idreq")) 

 req = in.readLine();
 for(int i=0;i<localArq.size();i++) //IDENTIFIES WHO OWNS THE REQUESTED FILE
 if(localArq.get(i).equals(req)) 

 System.out.println("Owns requested file");
 Socket requester = new Socket("192.168.3.114", 2007);
 ObjectOutputStream outputr = new ObjectOutputStream(requester.getOutputStream());
 ObjectInputStream inputr = new ObjectInputStream(requester.getInputStream());
 Object mens= inputr.readObject();
 System.out.println(mens);
 outputr.writeObject("OWNER FOUND");
 
 
 if(c==1) //IDENTIFIES WHO WANTS THE FILE
 rmsg = in.readLine();
 c= Integer.parseInt(rmsg);
 System.out.println("file: "+req);

 ServerSocket peer = new ServerSocket(2007);
 System.out.println("OPEN FOR CONNECTIONSn");

 Socket client = peer.accept();
 System.out.println("Client connected: " + client.getInetAddress().getHostAddress());
 ObjectOutputStream outputo = new ObjectOutputStream(client.getOutputStream());
 ObjectInputStream inputo = new ObjectInputStream(client.getInputStream());
 outputo.flush();
 outputo.writeObject("Connected to requester");
 Object mens= inputo.readObject();
 System.out.println(mens);

 

 
 else 
 System.out.println(rmsg);
 
 
 catch (IOException e) 
 e.printStackTrace();
 catch (ClassNotFoundException e) 
 e.printStackTrace();
 
 done = true;

I was able to make a transfer between two clients easily with the information provided and a little research on stackOverflow to understand more about out/inputStreams!
This post also helped me a lot: Sending a file with Java Sockets, losing data
next step is the shared transfer