private void login(String userName, char[] password){
		
		//load login information
		logAc = logAc.load(logAc);
		if ((mode = Doctor.checkLogin(db,logAc,userName,password))!=0){
			//when password match, saved mode : 1:Doctor 2:admin
			this.userName = userName;
			doctorID = userName;
			db = db.load(db);
			menuPage();
			cardLayout.show(contentPane, "Menu"); //change panel
			setJMenuBar(menubar); //show the menu bar
		}
		else
			JOptionPane.showMessageDialog(null, "Please retry","Login Failed", JOptionPane.ERROR_MESSAGE); //password not patch, show error message box
	}