Thread: could anybody fix my problem? resultset is closed

hello guys, i am new in java
could anyone help me with it? thanks before

here is my code:

String password = txPass.getText();
    String username = txUsername.getText(); 
 
    //int username1 = Integer.parseInt(username);
    //Double username1 = Double.parseDouble(username);
 
 
 
        try
        {
            String dbname="jdbc:odbc:Database";
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            Connection con = DriverManager.getConnection(dbname,"admin","admin");
            Statement s = con.createStatement();
            String sql = "SELECT * FROM admin where Username ='"+username+"' AND Password = '"+password+"' " ;
 
 
            ResultSet rs = s.executeQuery(sql);
 
 
            if (rs.next())
            {
                //throw new Exception();
                JOptionPane.showMessageDialog(null, "Login Sukses", "INFO", JOptionPane.INFORMATION_MESSAGE);
 
                Menu_admin admin = new Menu_admin();
                admin.setVisible(true);
                admin.setUser(rs.getString(1));
                dispose();
                //setVisible(false);
                //new Menu_admin().setVisible(true);
                rs.getStatement().close();
 
            } 
 
            else
            {
                try
                {
                    //Statement s = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
                    String skl = "SELECT* FROM mahasiswa where NIM ='"+username+"' AND password = '"+password+"' " ;
                    ResultSet rk = s.executeQuery(skl);
 
                    if (rk.next())
                    {
                        JOptionPane.showMessageDialog(null, "Login Sukses", "INFO", JOptionPane.INFORMATION_MESSAGE);
 
                        Menu_mhs mhs = new Menu_mhs();
                        mhs.setVisible(true);
                        mhs.setMhs(rs.getString(1));
                        dispose();
                        //new Menu_dsn().setVisible(true);
 
                    }
 
 
                    else
                    {
                        try
                        {
                            Statement b = con.createStatement();
                        String sjl = "SELECT* FROM dosen where NID ='"+username+"' AND password = '"+password+"' " ;
                        ResultSet rj = b.executeQuery(sjl);
 
                        if (rj.next())
                            {
                                JOptionPane.showMessageDialog(null, "Login Sukses", "INFO", JOptionPane.INFORMATION_MESSAGE);
 
                                Menu_dsn dsn = new Menu_dsn();
                                dsn.setVisible(true);
                                dsn.setUser(rs.getString(1));
                                dispose();
                                //new Menu_mhs().setVisible(true);
                            }
 
                        else
                            {
                                JOptionPane.showMessageDialog(null, "Username atau Password salah", "ERROR", JOptionPane.ERROR_MESSAGE);
                            }                                             
                        }
 
                        catch (Exception e)
                        {
                           JOptionPane.showMessageDialog(null,"Error:\n" +e,"ERROR",JOptionPane.WARNING_MESSAGE);            
                        }
                    }
                }
 
                catch (Exception e)
                {
                    JOptionPane.showMessageDialog(null,"Error:\n" +e,"ERROR",JOptionPane.WARNING_MESSAGE);                          
                }
            }
 
 
 
        }
        catch (Exception e)
        {
            JOptionPane.showMessageDialog(null,"Error:\n" +e,"ERROR",JOptionPane.WARNING_MESSAGE);
          // new Menu().setVisible(true);
        }