Java Utililty Methods TimeZone Create

DateFormat xpathTimezoneFormat = new SimpleDateFormat("Z");
String timeZone = xpathTimezoneFormat.format(date);
return timeZone.substring(0, timeZone.length() - 2) + ':' + timeZone.substring(timeZone.length() - 2);

StringBuilder buf = new StringBuilder();
TimeZone tz = cal.getTimeZone();
int offset = tz.getOffset(cal.getTimeInMillis());
int hours = Math.abs((offset / (60 * 1000)) / 60);
int minutes = Math.abs((offset / (60 * 1000)) % 60);
buf.append(offset < 0 ? '-' : '+');
buf.append(XX_FORMAT.format(hours));
buf.append(':');
...

if (id == null)
    return TimeZone.getDefault();
else
    return TimeZone.getTimeZone(id);

if (tzId == null) {
    throw new IllegalArgumentException("getTimeZone");
TimeZone tz = TimeZone.getTimeZone(tzId);
if (!tz.getID().equals(tzId)) {
    throw new IllegalArgumentException("getTimeZone");
return tz;
...

String[] timeZoneIds = TimeZone.getAvailableIDs(rawoffset);
if (timeZoneIds.length == 0) {
    return TimeZone.getDefault();
TimeZone result = TimeZone.getTimeZone(timeZoneIds[0]);
return null == result ? TimeZone.getDefault() : result;

if (id == null || id.length() == 0)
    return null;
TimeZone result = TimeZone.getTimeZone(id);
if ("GMT".equals(result.getID()) && !"GMT".equals(id))
    return null;
return result;

if (idParam == null || idParam.isEmpty()) {
    throw new IllegalArgumentException("id for time zone cannot be null or empty");
idParam = idParam.trim();
String[] tzArray = java.util.TimeZone.getAvailableIDs();
for (String id : tzArray) {
    if (id.equalsIgnoreCase(idParam)) {
        return java.util.TimeZone.getTimeZone(id);
...

timeZone = timeZone.trim();
TimeZone zone = TimeZone.getTimeZone(timeZone);
String id = zone.getID();
if (id.compareTo(timeZone) != 0) {
    throw new IllegalArgumentException("Bad timezone name: '" + timeZone + "'");
return zone;

if (timeZone.equalsIgnoreCase(LOCAL_TIME)) {
    return TimeZone.getDefault();
return TimeZone.getTimeZone(timeZone);

return TimeZone.getTimeZone(timeZoneId);