Java Utililty Methods Timestamp Create

Calendar today = new GregorianCalendar();
SimpleDateFormat df = new SimpleDateFormat();
df.applyPattern("yyyyMMDD_HHMMss");
return df.format(today.getTime());

DateFormat df = dfs.get();
if (df == null) {
    TimeZone tz = TimeZone.getTimeZone("UTC");
    df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
    df.setTimeZone(tz);
    dfs.set(df);
return df.format(new Date());
...

SimpleDateFormat pattern = new SimpleDateFormat("HHmmss");
Calendar now = Calendar.getInstance();
pattern.setCalendar(now);
return pattern.format(now.getTime());

if (timestamp == null) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd_HH.mm.ss");
    timestamp = dateFormat.format(new Date());
return timestamp;

return String.valueOf(new Date().getTime()).substring(0, 10);

DateFormat dateFormat = new SimpleDateFormat("yyyy.MM.dd hh:mm:ss:S");
return (dateFormat.format(new Date()));

String timeStamp = new SimpleDateFormat(TIMESTAMP_FORMAT).format(new Date());
return timeStamp;

calendar.add(Calendar.SECOND, random.nextInt(3));
String result = simpleDate.format(calendar.getTime());
return "[" + result + "]";

return new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy").format(new Date(System.currentTimeMillis()));

DateFormat dateFormat = new SimpleDateFormat("yy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
return dateFormat.format(cal.getTime()) + "-" + cal.getTimeInMillis();