testing = new Vector<AccountData>();
        testing.add(new AccountData("1234567A","1234567A"));
        testing.add(new AccountData("1234567B","1234567B"));
        testing.add(new AccountData("1234567C","1234567C"));
        testing.add(new AccountData("1234567D","1234567D"));
            }

    public AttendanceGUI() {

                        mainFrame = new JFrame();
                        mainFrame.setTitle("Student Attendance System");
                        mainFrame.setSize(400,150);
                        mainFrame.setLocation(100,100);
                        mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

                        addAccountData();

                        pTop = new JPanel();
                        pTop.setLayout(new GridLayout(3,2));

                        usernameEntry = new JTextField("Student ID");
                        passwordEntry = new JTextField("Matric Number");
                        username = new JLabel("Username",JLabel.LEFT);
                        password = new JLabel("Password",JLabel.LEFT);

                        bLogin = new JButton("Login");
                        bLogin.addActionListener(new ButtonHandler());

                        bClear = new JButton("Clear");
                        bClear.addActionListener(new ButtonHandler());

                        pTop.add(username);
                         pTop.add(usernameEntry);
                        pTop.add(password);
                        pTop.add(passwordEntry);
                        pTop.add(bLogin);
                        pTop.add(bClear);

                        mainFrame.add(pTop);
                        mainFrame.setVisible(true);
    }

        public static void main(String [] args)
        {
                JFrame.setDefaultLookAndFeelDecorated(true);
                AttendanceGUI attendanceSystem = new AttendanceGUI();
        }

        public class ButtonHandler implements ActionListener
        {
        String adminAccount="admin";
        String adminPassword="pass";
        int i=0;

                public void actionPerformed(ActionEvent evt)
                {
                                if(evt.getSource() == bLogin)
                                {
                                String studentID = usernameEntry.getText();
                                String studentPassword = passwordEntry.getText();
                                Vector<String> vec = new Vector<String>();
                                Date today = new Date();
                                loop: for(AccountData d: testing)
                                {
                                        if (studentID.compareToIgnoreCase(adminAccount) == 0 && studentPassword.compareToIgnoreCase(adminPassword) == 0)
                                        {
                                                String userlist = "User List:\n";
                                                loop2: for(AccountData e: testing)
                                                {
                                                        userlist = userlist + "Name: " + e.getStudentID();
                                                        userlist = userlist + "Login Date: " + e.getAttendance();
                                                        userlist = userlist + "\n";
                                                }
                                                JOptionPane.showMessageDialog(mainFrame, userlist , "Attendance List", JOptionPane.INFORMATION_MESSAGE);
                                                return;
                                        }
                                        else if (studentID.compareToIgnoreCase(d.getStudentID())==0 && studentPassword.compareToIgnoreCase(d.getStudentID())==0)
                                        {
                                                test[i]=today.toString();
                                                d.setAttendance(today.toString());
                                                JOptionPane.showMessageDialog(mainFrame, "Student ID: "+d.getStudentID()+" Login Date: "+today.toString() , "Attendance Marked", JOptionPane.INFORMATION_MESSAGE);
                                                return;
                                        }
                                }

                               JOptionPane.showMessageDialog(mainFrame, "Error: Invalid Login Information" , "Login Error", JOptionPane.INFORMATION_MESSAGE);

                                }
                                if(evt.getSource() == bClear)
                                {
                                        usernameEntry.setText("");
                                        passwordEntry.setText("");
                                }

                        }
        }

}