Java Utililty Methods Day of

String dateString = new SimpleDateFormat(SHORT_DATE_FORMAT_STR).format(date) + " " + LATE_TIME;
return new SimpleDateFormat(LONG_DATE_FORMAT_STR).parse(dateString);

String todayStr = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");
todayStr = sdf.format(new Date(System.currentTimeMillis()));
todayStr = todayStr + " 00:00:00";
Date today = new Date();
DateFormat sdf2 = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Map<String, Long[]> data = new TreeMap<>();
try {
...

try {
    Calendar c = Calendar.getInstance();
    Date date = parse(dateStr, dateFormat);
    c.setTime(date);
    c.add(c.DAY_OF_MONTH, n);
    return c.get(c.YEAR) + "-" + (c.get(c.MONTH) + 1) + "-" + c.get(c.DATE);
} catch (ParseException e) {
    e.printStackTrace();
...

return otherDayLastUpdateTimeFormat.get();

int i = -(3 + getRandomNumber(70));
Date date = new Date();
Calendar cal = Calendar.getInstance();
cal.add(Calendar.YEAR, i);
cal.add(Calendar.HOUR, getRandomNumber(50));
cal.add(Calendar.MONTH, getRandomNumber(9));
date = cal.getTime();
SimpleDateFormat df = new SimpleDateFormat("yyMMdd");
...

SimpleDateFormat timeFormat = new SimpleDateFormat(pattern);
Calendar theday = Calendar.getInstance();
theday.add(5, offset);
return timeFormat.format(theday.getTime());

long diff = (date.getTime() - sday.parse(line).getTime()) - 60 * 60 * 1000;
return new Date(diff);

StringBuffer str = new StringBuffer();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.DATE, dayNum);
str.append(sdf.format(lastDate.getTime()));
return str.toString();

Date date = new Date();
SimpleDateFormat datetr = new SimpleDateFormat("yyyyMMdd");
String lastSign = datetr.format(lastSignTime);
String nowDay = datetr.format(date);
int lastSignDay = Integer.parseInt(lastSign);
int newDay = Integer.parseInt(nowDay);
return newDay - lastSignDay;

Date[] dates = new Date[2];
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
try {
    dates[0] = sdf.parse(format(startDate, "yyyy-MM-dd"));
    Calendar calendar = new GregorianCalendar();
    calendar.setTime(dates[0]);
    calendar.add(Calendar.DATE, num);
    calendar.add(Calendar.SECOND, -1);
...