Java Utililty Methods Weekend

SimpleDateFormat sdf = new SimpleDateFormat(format);
return sdf.format(endOfWeek(date));

Calendar cal = Calendar.getInstance();
cal.setTime(date);
return new Integer(cal.get(Calendar.WEEK_OF_YEAR));

SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
dateFormat.parse(strDate, new ParsePosition(0));
Calendar calendar = dateFormat.getCalendar();
int day = calendar.get(Calendar.DAY_OF_WEEK);
calendar.add(Calendar.DATE, 7 - day);
return dateFormat.format(calendar.getTime());

List<String> ret = new ArrayList<String>();
Date beginDate = parseDate(strBeginDate);
Date endDate = parseDate(strEndDate);
String beginFormat = formatDate(beginDate, pattern);
String endFormat = formatDate(endDate, pattern);
ret.add(beginFormat);
while (!beginFormat.equals(endFormat)) {
    beginDate = addWeek(beginDate, 1);
...

return getWeekNumByDate(getCurrentDate_String()) == 0;

int dayInWeek = calendar.get(Calendar.DAY_OF_WEEK);
return dayInWeek == Calendar.SATURDAY || dayInWeek == Calendar.SUNDAY;

return (dateCal.get(Calendar.DAY_OF_WEEK) == Calendar.SATURDAY
        || dateCal.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY);

Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
int weekday = calendar.get(Calendar.DAY_OF_WEEK);
if (weekday == Calendar.SUNDAY || weekday == Calendar.SATURDAY)
    return true;
return false;

if (date != null) {
    Calendar calendar = Calendar.getInstance();
    calendar.setFirstDayOfWeek(Calendar.MONDAY);
    calendar.setTime(date);
    int dayOfTheWeek = calendar.get(Calendar.DAY_OF_WEEK);
    return dayOfTheWeek == Calendar.SATURDAY || dayOfTheWeek == Calendar.SUNDAY;
} else {
    return false;
...

Calendar cal = new GregorianCalendar();
cal.setTime(datum);
int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
return dayOfWeek == Calendar.SATURDAY || dayOfWeek == Calendar.SUNDAY;