Java Utililty Methods Time in GMT

FORMAT.setTimeZone(TimeZone.getTimeZone("GMT"));
String dateString = FORMAT.format(date);
return dateString;

Date gmt8 = null;
try {
    Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("GMT+8"), Locale.CHINESE);
    Calendar day = Calendar.getInstance();
    day.set(Calendar.YEAR, cal.get(Calendar.YEAR));
    day.set(Calendar.MONTH, cal.get(Calendar.MONTH));
    day.set(Calendar.DATE, cal.get(Calendar.DATE));
    day.set(Calendar.HOUR_OF_DAY, cal.get(Calendar.HOUR_OF_DAY));
...

String gmt = null;
if (null == tm || "Default".equals(tm)) {
    return getDefaultID2GMT();
for (Entry<String, StringBuffer> en : normtoIDsMap.entrySet()) {
    String enKey = en.getValue().toString();
    if (enKey.indexOf(tm) >= 0 || enKey.equalsIgnoreCase(tm)) {
        gmt = en.getKey();
...

SimpleDateFormat dtFormat = new SimpleDateFormat(m_sDtFormat);
Calendar newDate = getGMTCalendar();
newDate.setTime(dtFormat.parse(sTime));
return newDate;

SimpleDateFormat sdf = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss 'GMT'", Locale.US);
sdf.setTimeZone(TimeZone.getTimeZone("GMT"));
return sdf.format(new Date());

SimpleDateFormat df = new SimpleDateFormat(format);
df.setTimeZone(TimeZone.getTimeZone("GMT"));
return df;

SimpleDateFormat format = new SimpleDateFormat(strFormat);
format.setCalendar(getGMTCalendar());
return format;

SimpleDateFormat formatter = (SimpleDateFormat) DateFormat.getDateInstance();
TimeZone gmt = TimeZone.getTimeZone("GMT");
formatter.setTimeZone(gmt);
formatter.applyPattern("dd MMMM");
String dayString = formatter.format(date);
formatter = (SimpleDateFormat) DateFormat.getTimeInstance();
formatter.setTimeZone(gmt);
formatter.applyPattern("hh:mm zzz yyyy");
...

return RFC_822_DATE_FORMAT.get().format(datetime);

return new SimpleDateFormat(GMT_DATETIME_FORMAT_PATTERN);