[Java] Performance Problem beim Senden über netzwerk

File fts = new File(command.substring(5));

 sock = new java.net.Socket(serverIPname, serverPort); // create socket and connect

 br = new java.io.BufferedReader(new java.io.InputStreamReader(sock.getInputStream()));

 pw = new java.io.PrintWriter(sock.getOutputStream(), true); // create reader and writer 

 out("Connected to Server");

 pw.println("send " + fts.getName());


 DataOutputStream dos = new DataOutputStream(sock.getOutputStream());

 FileInputStream fis = new FileInputStream(fts);

 jProgressBar1.setMaximum(fis.available());
//hier ist das senden
 Rectangle progressRect = null;
 int i = 0;
 int count = 0;
 while ((i = fis.read()) != -1) {
 dos.write(i);
 count++;
 jProgressBar1.setValue(count);
 progressRect = jProgressBar1.getBounds();
 progressRect.x = 0;
 progressRect.y = 0;
 jProgressBar1.paintImmediately(progressRect);
 }

 dos.flush();
 dos.close();
 fis.close();

 out("Datei gesendet!");

 pw.close(); // close everything

 br.close();

 sock.close();

 out("Connection closed");

is = new DataInputStream(clientSocket.getInputStream());
 File tmpFile = new File(filename);
 FileOutputStream fos = new FileOutputStream(tmpFile);

 System.out.println("Recieving File >" + filename);

 int i = 0;
 while ((i = is.read()) != -1) {
 fos.write(i);
 }
 fos.flush();
 fos.close();
 is.close();

 System.out.println("File Recieved >" + filename);
 pw.println("File Recieved >" + filename);