Java Utililty Methods TimeZone Format

void addDateFormatsToList(Locale locale, TimeZone timeZone, List formats)
add Date Formats To List

for (int dateStyle = DateFormat.FULL; dateStyle <= DateFormat.SHORT; dateStyle++) {
 DateFormat df = DateFormat.getDateInstance(dateStyle, locale);
 df.setTimeZone(timeZone);
 formats.add(df);

DateFormat createDateFormat(String format, TimeZone tz)
create Date Format

SimpleDateFormat sdf = new SimpleDateFormat(format);
sdf.setTimeZone(tz);
sdf.setDateFormatSymbols(new DateFormatSymbols(Locale.US));
return sdf;

DateFormat createDateFormat(String pattern, TimeZone timeZone)
create Date Format

return createDateFormat(pattern, timeZone, false);

DateFormat createDateFormat(TimeZone timezone)
create Date Format

SimpleDateFormat sdf = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z", Locale.US);
sdf.setTimeZone(timezone);
return sdf;

DateFormat[] createDateFormatsForLocaleAndTimeZone(Locale locale, TimeZone timeZone)
Build an array of DateFormats that are commonly used for this locale and timezone.

List<DateFormat> formats = new ArrayList<DateFormat>();
addDateTimeFormatsToList(locale, timeZone, formats);
addDateFormatsToList(locale, timeZone, formats);
return formats.toArray(new DateFormat[formats.size()]);

String formatISO8601TimeZone(TimeZone timeZone, boolean extended)

Converts a TimeZone object to a string that's in ISO-8601 format.

StringBuilder sb = new StringBuilder();
boolean positive = timeZone.getRawOffset() >= 0;
int hours = Math.abs(((timeZone.getRawOffset() / 1000) / 60) / 60);
int minutes = Math.abs((timeZone.getRawOffset() / 1000) / 60) % 60;
sb.append(positive ? '+' : '-');
if (hours < 10) {
 sb.append('0');
sb.append(hours);
if (extended) {
 sb.append(':');
if (minutes < 10) {
 sb.append('0');
sb.append(minutes);
return sb.toString();

String formatOffset(TimeZone zone)
Produce a string describing the offset of the given time zone from UTC, including the DST offset if there is one.

String fmt = "";
int base = zone.getRawOffset();
fmt += "UTC" + intervalMsToHmsShort(base);
int dst = zone.getDSTSavings();
if (dst != 0)
 fmt += " (UTC" + intervalMsToHmsShort(base + dst) + ")";
return fmt;

String formatTimeZoneOffset(TimeZone timeZone)
Returns the formatted offset of the specified time zone at the current local time.

int offsetSeconds = timeZone.getOffset(System.currentTimeMillis()) / 1000;
int offsetHours = Math.abs(offsetSeconds / 3600);
int offsetMinutes = (Math.abs(offsetSeconds) - (offsetHours * 3600)) / 60;
StringBuilder offset = new StringBuilder("UTC");
if (offsetSeconds >= 0) {
 offset.append('+');
} else {
 offset.append('-');
...

Calendar getCalendar(String dateString, String dateTimeFormat, String timeZoneName)
get Calendar

DateFormat dateFormat = new SimpleDateFormat(dateTimeFormat);
dateFormat.setTimeZone(TimeZone.getTimeZone(timeZoneName));
Calendar disbursementCalendar = Calendar.getInstance(TimeZone.getTimeZone(timeZoneName));
disbursementCalendar.setTime(dateFormat.parse(dateString));
return disbursementCalendar;

Calendar getCalendar(String dateString, String format, TimeZone tz)
get Calendar

if (dateString == null || format == null || dateString.equals("") || tz == null)
 return null;
Calendar cal = null;
try {
 Date date = getDate(dateString, format, tz);
 cal = Calendar.getInstance();
 cal.setTime(date);
} catch (Exception ex) {
...