Java JSpinner.DateEditor working with TimeZone March clock change

Question

I have a problem with the standard JSpinner.DateEditor (as probably does everyone else). When it works with the Java.util.Date class, it only gets a default format from the Locale set on the spinner. It appears to be TimeZone ignorant.

When we have a Date that is on the March Clock change day which in the UK has no 2 o'clock - the time jumps from 01:59:59.999 AM to 03:00 AM with day light savings applied.

Therefore in the JSpinner.DateEditor I do not want the user to see anything for 02:00 to 02:59:59.999. When the hour is on 1 and they click up, I want to jump to 3 and vice versa.

Is it possible to implement any kind of workaround to do this?

Many thanks

Andez

Answer 1

can you please edit your question and use this SSCCE that demonstrating your issue about DTS

import java.awt.*;
import java.text.SimpleDateFormat;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;

public class TimeZoneSpinners {

    private final String[] zones = {"Asia/Tokyo", "Asia/Hong_Kong",
        "Asia/Calcutta", "Europe/Paris", "Europe/London",
        "America/New_York", "America/Los_Angeles"
    };
    private final JLabel[] labels = new JLabel[zones.length];
    private final SimpleDateFormat[] formats = new SimpleDateFormat[zones.length];
    private JSpinner spinner;
    private SpinnerDateModel model;
    private SimpleDateFormat format;
    private JPanel panel;
    private JFrame frame = new JFrame();

    public void makeUI() {
        Calendar cal = Calendar.getInstance();
        Date date = cal.getTime();
        model = new SpinnerDateModel();
        model.setValue(date);
        spinner = new JSpinner(model);
        spinner.addChangeListener(new ChangeListener() {

            @Override
            public void stateChanged(ChangeEvent e) {
                Date date = (Date) ((JSpinner) e.getSource()).getValue();
                for (int i = 0; i < labels.length; i++) {
                    labels[i].setText(formats[i].format(date));
                }
            }
        });
        format = ((JSpinner.DateEditor) spinner.getEditor()).getFormat();
        format.setTimeZone(TimeZone.getTimeZone(zones[0]));
        format.applyPattern("yyyy-MM-dd 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].setTimeZone(TimeZone.getTimeZone(zones[i]));
            JLabel label = new JLabel(zones[i]);
            labels[i] = new JLabel(formats[i].format(date));
            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) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new TimeZoneSpinners().makeUI();
            }
        });
    }
}

Answer 2

After reading mKorbels solution, I used it to essentially get what I wanted. I have modified the code to the following:

package datesandtimes.javax.swing;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.SimpleTimeZone;
import java.util.TimeZone;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.SpinnerDateModel;
import javax.swing.SwingUtilities;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

public class JSpinnerProblem
        extends JFrame {

    static {
        TimeZone simpleTimeZone = new SimpleTimeZone(0, "Elexon Date Time");
        TimeZone.setDefault(simpleTimeZone);
    }

    private static final String DATE_FORMAT_TIMEZONE = "yyyy-MM-dd HH:mm:ss zzz";
    private static final TimeZone tz = TimeZone.getTimeZone("Europe/London");    

    private JPanel panel; 
    private JPanel panelButtons; 
    private JSpinner spinner;
    private SpinnerDateModel model;
    private SimpleDateFormat format;
    private JButton buttonClose;

    public JSpinnerProblem() {
        try {
            setDefaultCloseOperation(JSpinnerProblem.EXIT_ON_CLOSE);
            setLayout(new BorderLayout(5, 5));

            // create instances
            panel = new JPanel(new BorderLayout());
            panelButtons = new JPanel(new GridLayout(1, 1));
            model = new SpinnerDateModel();
            buttonClose = new JButton("Close");

            spinner = new JSpinner(model);
            spinner.addChangeListener(new ChangeListener() {

                @Override
                public void stateChanged(ChangeEvent e) {

                }
            });

            buttonClose.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    System.exit(0);
                }
            });

            // set date format
            format = ((JSpinner.DateEditor) spinner.getEditor()).getFormat(); 
            format.setTimeZone(tz);
            format.applyPattern("yyyy-MM-dd HH:mm:ss zzz");

            // default to march clock change
            Date d = format.parse("2012-03-25 00:00:00 GMT");
            model.setValue(d);

            panel.add(spinner, BorderLayout.CENTER);
            panelButtons.add(buttonClose);

            add(panel, BorderLayout.CENTER);
            add(panelButtons, BorderLayout.SOUTH);
            pack();

        } catch (ParseException ex) {
            ex.printStackTrace();
        }
    }


    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new JSpinnerProblem().setVisible(true);
            }
        });
    }

}

Now when using the JSpinner, clicking the up and down buttons actually changes the hour to the correct hour based on the time zone.