Java tutorial
import java.awt.BorderLayout; import java.awt.GridLayout; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.TimeZone; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JSpinner; import javax.swing.SpinnerDateModel; public class Main { String[] zones = { "Asia/Tokyo", "Asia/Hong_Kong", "Asia/Calcutta", "Europe/Paris", "Europe/London", "America/New_York", "America/Los_Angeles" }; JLabel[] labels = new JLabel[zones.length]; SimpleDateFormat[] formats = new SimpleDateFormat[zones.length]; JSpinner spinner; SpinnerDateModel model = new SpinnerDateModel(); SimpleDateFormat format; JPanel panel; JFrame frame = new JFrame(); public Main() { Calendar cal = Calendar.getInstance(); Date date = cal.getTime(); model.setValue(date); spinner = new JSpinner(model); spinner.addChangeListener(e -> { Date d = (Date) ((JSpinner) e.getSource()).getValue(); for (int i = 0; i < labels.length; i++) { labels[i].setText(formats[i].format(d)); } }); format = ((JSpinner.DateEditor) spinner.getEditor()).getFormat(); format.setTimeZone(TimeZone.getTimeZone(zones[0])); format.applyPattern("yyyy-MM-dd HH:mm:ss"); format.applyPattern("HH:mm:ss"); panel = new JPanel(new GridLayout(zones.length, 2, 10, 10)); for (int i = 0; i < zones.length; i++) { formats[i] = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss"); formats[i] = new SimpleDateFormat("HH:mm:ss"); formats[i].setTimeZone(TimeZone.getTimeZone(zones[i])); JLabel label = new JLabel(zones[i]); labels[i] = new JLabel(formats[i].format(date)); labels[i].setHorizontalAlignment(JLabel.RIGHT); panel.add(label); panel.add(labels[i]); } frame.setLayout(new BorderLayout(10, 10)); frame.add(spinner, BorderLayout.NORTH); frame.add(panel, BorderLayout.CENTER); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.pack(); frame.setVisible(true); } public static void main(String[] args) { new Main(); } }