Uso RMI e soquete para transferir arquivos entre um conjunto de clientes. O problema está ao executar o código abaixoas vezes Eu recebo essa exceção no lado do cliente:

java.io.EOFException
at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2671)
at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:3146)
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:858)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java:354)
at javafxcyberwind.serverSocket.run(serverSocket.java:38)
at java.lang.Thread.run(Thread.java:748)

Este é um exemplo do meu código, as exceções estão nas linhas de comentário:

Cliente :

Server_MethodsPEER S = (Server_MethodsPEER) Naming.lookup("rmi://" + ip + ":" + port + "/" + email);
Server_Methods R = S.peer();
R.uploadToServer(fileName);
Socket s = new Socket(ip, R.getServerSocketPort());
File fres = new File(crep + fileName);
FileInputStream inf = new FileInputStream(fres);
ObjectOutputStream out = new ObjectOutputStream(s.getOutputStream());
byte buf[] = new byte[1024];
int nn;
while ((nn = inf.read(buf)) != -1) {
    out.write(buf, 0, nn);
}
out.close();
inf.close();
s.close();
fres.delete();

Servidor :

public class serverSocket implements Runnable {

private final ServerSocket socketserver;
private Socket socket;
private final String ff;
private final String rp;

public serverSocket(ServerSocket s, String file, String rep) {
    socketserver = s;
    ff = file;
    rp = rep;
}

@Override
public void run() {
    try {
        socket = socketserver.accept();
        ObjectInputStream in = new ObjectInputStream(socket.getInputStream());//EOFException here
        FileOutputStream out = new FileOutputStream(new File(rp + ff));
        byte buf[] = new byte[1024];
        int n;
        while ((n = in.read(buf)) != -1) {
            out.write(buf, 0, n);
        }
        in.close();
        out.close();
        socket.close();
        socketserver.close();
    } catch (IOException e) {
        System.err.println("socket err");
    }
}
}

//ServerIMPL
ServerSocket sv;

public void uploadToServer(String fileName) throws RemoteException {
    try {
        sv = new ServerSocket(0);
    } catch (IOException ex) {
        Logger.getLogger(Cloud_ServeurIMPL.class.getName()).log(Level.SEVERE, null, ex);
    }
    Thread t = new Thread(new serverSocket(sv, file, crep));
    t.start();

    Client3_MethodsPEER M = (Client3_MethodsPEER) Naming.lookup("rmi://" + ip + ":" + port + "/" + email);
    Client3_Methods U = M.peer();
    U.uploadToServer(fileName);
    Socket s = new Socket(ip, U.getServerSocketPort());
    File fres = new File(crep + fileName);
    FileInputStream inf = new FileInputStream(fres);
    ObjectOutputStream out = new ObjectOutputStream(s.getOutputStream());
    byte buf[] = new byte[1024];
    int nn;
    while ((nn = inf.read(buf)) != -1) {
        out.write(buf, 0, nn);
    }
    out.close();
    inf.close();
    s.close();
    fres.delete();
    U.operation();//FileNotFoundException here (use the received files as arguments)
}

Tudo parece estar bem. Por que isso está acontecendo e como resolvê-lo?