@Override
        public void appendTo(StringBuffer buffer, Calendar calendar) {
            TimeZone timeZone;
            if ((timeZone = mTimeZone) != null) {
                if (timeZone.useDaylightTime() &&
                    calendar.get(Calendar.DST_OFFSET) != 0) {

                    buffer.append(mDaylight);
                }
                else {
                    buffer.append(mStandard);
                }
            }
            else {
                timeZone = calendar.getTimeZone();
                if (timeZone.useDaylightTime() &&
                    calendar.get(Calendar.DST_OFFSET) != 0) {

                    buffer.append(getTimeZoneDisplay
                                  (timeZone, true, mStyle, mLocale));
                }
                else {
                    buffer.append(getTimeZoneDisplay
                                  (timeZone, false, mStyle, mLocale));
                }
            }
        }
Returns an estimate for the maximum length date that this date
formatter will produce. The actual formatted length will almost always
be less than or equal to this amount.
@return an estimate of the maximum length
xmppserver/src/main/java/org/jivesoftware/util/FastDateFormat.java