basic_clock.java

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.FlowLayout;
import java.util.Calendar;
import java.util.Date;
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.Font;

public class basic_clock extends JFrame
{
    JLabel date, time;

    public basic_clock()
    {
        super("clock");

        ActionListener listener = new ActionListener()
        {
            public void actionPerformed(ActionEvent event)
            {
                Calendar current = Calendar.getInstance();
                current.setTime(new Date());
                date.setText((current.get(Calendar.MONTH) + 1) +"/" +current.get(Calendar.DATE) +"/" +current.get(Calendar.YEAR));
                String timeStr = String.format("%d:%02d:%02d", current.get(Calendar.HOUR), current.get(Calendar.MINUTE), current.get(Calendar.SECOND));
                time.setText(timeStr);                
            }
        };

        date = new JLabel();
        time = new JLabel();

        setLayout(new FlowLayout());
        setSize(310,190);
        setResizable(false);
        setVisible(true);

        add(date);
        add(time);

        date.setFont(new Font("Arial", Font.BOLD, 64));
        time.setFont(new Font("Arial", Font.BOLD, 64));

        javax.swing.Timer timer = new javax.swing.Timer(500, listener);
        timer.setInitialDelay(0);
        timer.start();
    }

    public static void main(String args[])
    {

        basic_clock c = new basic_clock();
        c.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}