Socket connection in Java fails in the browser

when i run the code below in netbeans or eclipse it works, but when i put the applet in the browser it doesn't work. Please help me !

the applet for registration:


package newpackage;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JRadioButton;
import javax.swing.JTextField;
import javax.swing.plaf.basic.BasicBorders;


public class registracija extends JApplet{
    JTextField ime,prezime,embg,e_poshta,den,godina,korisnickoIme;
    Server server;
    Klient klient;
    JPasswordField lozinka;
    String meseci[]={"-Izberi-","Januari","Fevruari","Mart","April","Maj","Juni","Juli","Avgust","Septemvri","Oktomvri","Noemvri","Dekemvri"};
    JRadioButton m,zh;
    JButton zavrshi;
    JLabel jl,jl1,jl2,jl3,jl4,jl5,jl6,jl7,jl8,jl9;
    JComboBox jcb;

    @Override
    public void init(){   
        setSize(350, 370);
        server=null;
        klient=null;
        setLayout(new GridLayout(12, 1));
        lozinka=new JPasswordField();       
        JPanel p1=new JPanel(new FlowLayout(FlowLayout.LEFT)),p2=new JPanel(new FlowLayout(FlowLayout.LEFT)),p3=new JPanel(new FlowLayout(FlowLayout.LEFT)),p4=new JPanel(new FlowLayout(FlowLayout.LEFT)),p5=new JPanel(new FlowLayout(FlowLayout.RIGHT)),p7=new JPanel(new FlowLayout(FlowLayout.LEFT)),p8=new JPanel(new FlowLayout(FlowLayout.LEFT)),p9=new JPanel(new FlowLayout(FlowLayout.RIGHT)),p6=new JPanel(new FlowLayout());

        jl1=new JLabel();jl2=new JLabel();jl3=new JLabel();jl4=new JLabel();jl5=new JLabel();jl6=new JLabel();jl7=new JLabel();jl8=new JLabel();
        jl1.setForeground(Color.red);jl3.setForeground(Color.red);jl5.setForeground(Color.red);jl7.setForeground(Color.red);jl8.setForeground(Color.red);
        jl2.setForeground(Color.red);jl4.setForeground(Color.red);jl6.setForeground(Color.red);

        p1.add(new JLabel("Ime:                     "));
        ime=new JTextField();
        ime.setBounds(5, 5, 100, 100);
        ime.setPreferredSize(new Dimension(110,20));p1.add(ime);p1.add(jl1);
        add(p1);

        p2.add(new JLabel("Prezme:             "));
        prezime=new JTextField();p2.add(prezime);p2.add(jl2);add(p2);
        prezime.setBounds(5, 5, 100, 100);
        prezime.setPreferredSize(new Dimension(110,20));

        p3.add(new JLabel("EMBG:                 "));
        embg=new JTextField();p3.add(embg);p3.add(jl3);add(p3);
        embg.setBounds(5, 5, 100, 100);
        embg.setPreferredSize(new Dimension(110,20));

        p4.add(new JLabel("E-Poshta:           "));
        e_poshta=new JTextField();p4.add(e_poshta);p4.add(jl4);add(p4);
        e_poshta.setBounds(5, 5, 100, 100);
        e_poshta.setPreferredSize(new Dimension(110,20));

        korisnickoIme=new JTextField(); 
        p7.add(new JLabel("    Korisnicko ime:"));p7.add(korisnickoIme);p7.add(jl5);add(p7);        
        korisnickoIme.setBounds(5, 5, 100, 100);
        korisnickoIme.setPreferredSize(new Dimension(110,20));

        p8.add(new JLabel("    Lozinka:              "));p8.add(lozinka);p8.add(jl6);
        lozinka.setBounds(5, 5, 100, 100);
        lozinka.setPreferredSize(new Dimension(110,20));add(p8);

        JPanel panela=new JPanel(new FlowLayout(FlowLayout.LEFT));
        add(new JLabel("Pol"));
        m=new JRadioButton("Mashki");zh=new JRadioButton("Zhenski");
        panela.add(m);panela.add(zh);
        add(panela);
        add(new JLabel("Den Na Ragjanje"));
        JPanel panela1=new JPanel(new GridLayout(1,3));
        jcb=new JComboBox(meseci);
        den=new JTextField("den");godina=new JTextField("godina");
        den.setFont(new Font("Serif", Font.ITALIC, 14));
        godina.setFont(new Font("Serif", Font.ITALIC, 14));
        den.addMouseListener(new mousenter(den));
        godina.addMouseListener(new mousenter(godina));
        panela1.add(jcb);panela1.add(den);panela1.add(godina);
        add(panela1);   

        jl=new JLabel();p6.add(jl);
        jl.setForeground(Color.red);
        add(p6);

        zavrshi=new JButton("Zavrshi");
        add(p5);
        p5.add(zavrshi);
        zavrshi.addMouseListener(new MouseAdapter() {
            @Override
            public void mousePressed(MouseEvent event) {
                if(ime.getText().isEmpty()){
                    jl.setText("Vnesi go Imeto");
                    jl1.setText("*");
                }else if(prezime.getText().isEmpty()){
                     jl.setText("Vnesi go Prezimeto");
                     jl2.setText("*");
                }else if(embg.getText().isEmpty()){
                     jl.setText("Vnesi embg");
                     jl3.setText("*");
                }else if(e_poshta.getText().isEmpty()){
                     jl.setText("Vnesi e_poshta");
                     jl4.setText("*");
                }else if(korisnickoIme.getText().isEmpty()){
                     jl.setText("Vnesi Korisnicko Ime");
                     jl5.setText("*");
                }else if(lozinka.getText().isEmpty()){
                     jl.setText("Vnesi ja Lozinkata");
                     jl6.setText("*");
                }else if(!(m.isSelected() || zh.isSelected())){
                    jl.setText("Izberi Pol");
                }else if(jcb.getSelectedIndex()==0 || den.getText().equals("den") || godina.getText().equals("godina")){
                    jl.setText("Ispolni go datumot na radjanje");
                }else{
                    jl.setText("");jl1.setText("");jl2.setText("");jl3.setText("");jl4.setText("");jl5.setText("");jl6.setText("");jl7.setText("");jl8.setText("");
                    Korisnici korisnik=new Korisnici(ime.getText(), prezime.getText(), embg.getText(), e_poshta.getText(), korisnickoIme.getText(), lozinka.getText(), true, Integer.parseInt(den.getText()), (String)jcb.getSelectedItem(), Integer.parseInt(godina.getText()));
                    if(server==null){
                    server=new Server(jl);
                    server.start();
                    klient=new Klient(korisnik,jl);
                    klient.start();
                    }else{
                        try {
                            klient.setk(korisnik);
                        } catch (IOException ex) {
                            Logger.getLogger(registracija.class.getName()).log(Level.SEVERE, null, ex);
                        }
                    }



                }
            }
        });

    }


}

class mousenter implements MouseListener{
    JTextField jtf;

    public mousenter(JTextField jtf) {
        this.jtf = jtf;
    }

    @Override
    public void mouseClicked(MouseEvent me) {

    }

    @Override
    public void mousePressed(MouseEvent me) {
         jtf.setText("");jtf.setFont(new Font("Serif", Font.BOLD, 14));
    }

    @Override
    public void mouseReleased(MouseEvent me) {
    }

    @Override
    public void mouseEntered(MouseEvent me) {

    }

    @Override
    public void mouseExited(MouseEvent me) {
    }

}




the server class:


package newpackage;

import java.io.EOFException;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JLabel;
import javax.swing.JTextField;

public class Server extends Thread{

    private ObjectOutputStream output;
    private ObjectInputStream input;
    private ServerSocket server;
    private Socket connection;
    String whath;JLabel jl1;
    public Server(JLabel jl) {
        jl1=jl;
       // jl1.setText("da raboti");
    }


    private void waitForConnection() throws IOException {
        connection = server.accept();
     //   jl1.setText("connected");
    }

    private void setupStreams() throws IOException {
        output = new ObjectOutputStream(connection.getOutputStream());
        output.flush();
        input = new ObjectInputStream(connection.getInputStream());
    }

    private void proveriIregistriraj() throws IOException, ClassNotFoundException {
//        Korisnici k=(Korisnici) input.readObject();
//        System.out.println("proveriIregistri.:"+ k.ime);
        Korisnici korisnik=null;

        try {
            korisnik = (Korisnici) input.readObject();
//            System.out.println("hello ");
            if(korisnik!=null){
            ArrayList<Korisnici> al = new ArrayList<Korisnici>();
            try {
                FileInputStream fileIn =
                        new FileInputStream("korisnici.ser");
                ObjectInputStream in = new ObjectInputStream(fileIn);

                Korisnici kl = null;

                int count = 0;
                try {
                    while (true) {
                        count++;
                        try {
                            Korisnici obj = (Korisnici) in.readObject();
                            al.add(obj);
                        } catch (ClassNotFoundException e) {
                            System.out.println("can't read obj #" + count + ": " + e);
                        }
                    }
                } catch (EOFException e) {
                } catch (IOException e) {
                    System.out.println("A");
                } finally {
                    in.close();
                }



            } catch (Exception e) {
            }

            boolean flag=true;

            for(Korisnici kk : al){
                if(kk.korisnickoIme.equals(korisnik.korisnickoIme)){
                    flag=false;break;
                }
            }

            try {
                ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("korisnici.ser"));
                for (Korisnici k : al) {
                    out.writeObject(k);
                }
                if(flag){
                    out.writeObject(korisnik);
                    output.writeObject("OK");
                }
                else{
                    output.writeObject("WRONG");
                }

            } catch (Exception e) {
            }

            }

        } catch (ClassNotFoundException classNotFoundException) {
        }

    }

    public void closeCrap() {
        try {
            output.close();
            input.close();
            connection.close();
        } catch (IOException ioException) {
            ioException.printStackTrace();
        }
    }

    @Override
    public void run() {
        try {
            server = new ServerSocket(9999, 100);
           // jl1.setText("server created");
            while (true) {
                try {
                    waitForConnection();
                    setupStreams();
                    try {
                        proveriIregistriraj();
                    } catch (ClassNotFoundException ex) {
                        Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
                    }
                } catch (EOFException eofException) {
                } finally {
                    //closeCrap();
                }
            }
        } catch (IOException ioException) {
            ioException.printStackTrace();
        }
    }
}


the client class:

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package newpackage;

import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.Socket;
import javax.swing.JLabel;



public class Klient extends Thread{

   private ObjectOutputStream output;
   private ObjectInputStream input;   
   private Socket connection;
   Korisnici korisnici;
   JLabel jl;
    public Klient(Korisnici korisnici,JLabel jl) {
        this.korisnici=korisnici;
        this.jl=jl;
      //  jl.setText("do tuka bilo");
    }

   public void startRunning(){

   }
   public void setk(Korisnici k) throws IOException{
       korisnici=k;
       run();
   }
   private void connectToServer() throws IOException{
      connection = new Socket("localhost", 9999);
   }

   //set up streams to send and receive messages
   private void setupStreams() throws IOException{
      output = new ObjectOutputStream(connection.getOutputStream());
      output.flush();
      input = new ObjectInputStream(connection.getInputStream());
   }

   //while chatting with server
   private void prati() throws IOException{
      // output.writeObject(korisnici);
    //  jl.setText("prati");
       try{
//           jl.setText("before");
         output.writeObject(korisnici);
//         jl.setText("after");
         output.flush();
      }catch(IOException ioException){
//          jl.setText("in catch");
      }
       String s=null;
         try{

              s=(String) input.readObject();
             if(s!=null && s.equals("WRONG") )
                 jl.setText("Korisnickoto ime veqe postoi");

         }catch(ClassNotFoundException classNotfoundException){

         }


   }


    public void closeCrap(){
      try{
         output.close();
         input.close();
         connection.close();
      }catch(IOException ioException){
         ioException.printStackTrace();
      }
   }

    @Override
    public void run() {
        try{
            jl.setText("try to connect");
         connectToServer();
         jl.setText("connected client");
         setupStreams();
          prati();
      }catch(EOFException eofException){
      }catch(IOException ioException){
         ioException.printStackTrace();
      }finally{
       //  closeCrap();
      }
    }

}


the user class:

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package newpackage;

import java.io.Serializable;

public class Korisnici implements Serializable{
    String ime,prezime,embg,e_poshta,korisnickoIme,lozinka,mesecR;
    boolean mashkiRod;
    int denR,godinaR;

    public Korisnici(String ime, String prezime, String embg, String e_poshta, String korisnickoIme, String lozinka, boolean mashkiRod, int denR, String mesecR, int godinaR) {
        this.ime = ime;
        this.prezime = prezime;
        this.embg = embg;
        this.e_poshta = e_poshta;
        this.korisnickoIme = korisnickoIme;
        this.lozinka = lozinka;
        this.mashkiRod = mashkiRod;
        this.denR = denR;
        this.mesecR = mesecR;
        this.godinaR = godinaR;
    }

    public String getIme() {
        return ime;
    }

    public String getPrezime() {
        return prezime;
    }

    public String getEmbg() {
        return embg;
    }

    public String getE_poshta() {
        return e_poshta;
    }

    public String getKorisnickoIme() {
        return korisnickoIme;
    }

    public String getLozinka() {
        return lozinka;
    }

    public boolean isMashkiRod() {
        return mashkiRod;
    }

    public int getDenR() {
        return denR;
    }

    public String getMesecR() {
        return mesecR;
    }

    public int getGodinaR() {
        return godinaR;
    }

}

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