Time: How to get the next friday ?
java.time
In the java 8 and later versions we have framework called java.time. Here ,in order to get the next or previous day-of-week we can use TemporalAdjusters.
private LocalDate calcNextFriday(LocalDate d) { return d.with(TemporalAdjusters.next(DayOfWeek.FRIDAY)); }
Try to use this code,
private LocalDate calcNextFriday3(LocalDate d) { return d.isBefore(d.dayOfWeek().setCopy(5))?d.dayOfWeek().setCopy(5):d.plusWeeks(1).dayOfWeek().setCopy(5); }
Otherwise use this one,
private LocalDate calcNextDay(LocalDate d, int weekday) { return (d.getDayOfWeek() < weekday)?d.withDayOfWeek(weekday):d.plusWeeks(1).withDayOfWeek(weekday); } private LocalDate calcNextFriday2(LocalDate d) { return calcNextDay(d,DateTimeConstants.FRIDAY); }
if (d.getDayOfWeek() < DateTimeConstants.FRIDAY) { return d.withDayOfWeek(DateTimeConstants.FRIDAY)); } else if (d.getDayOfWeek() == DateTimeConstants.FRIDAY) { // almost useless branch, could be merged with the one above return d; } else { return d.plusWeeks(1).withDayOfWeek(DateTimeConstants.FRIDAY)); }
another simple kind of approach,
private LocalDate calcNextFriday(LocalDate d) { if (d.getDayOfWeek() < DateTimeConstants.FRIDAY) { d = d.withDayOfWeek(DateTimeConstants.FRIDAY)); } else { d = d.plusWeeks(1).withDayOfWeek(DateTimeConstants.FRIDAY)); } return d; // note that there's a possibility original object is returned }
More short form,
private LocalDate calcNextFriday(LocalDate d) { if (d.getDayOfWeek() >= DateTimeConstants.FRIDAY) { d = d.plusWeeks(1); } return d.withDayOfWeek(DateTimeConstants.FRIDAY); }
It’s possible to do it in a much easier to read way:
if (d.getDayOfWeek() < DateTimeConstants.FRIDAY) {
return d.withDayOfWeek(DateTimeConstants.FRIDAY));
} else if (d.getDayOfWeek() == DateTimeConstants.FRIDAY) {
// almost useless branch, could be merged with the one above
return d;
} else {
return d.plusWeeks(1).withDayOfWeek(DateTimeConstants.FRIDAY));
}
or in a bit shorter form
private LocalDate calcNextFriday(LocalDate d) {
if (d.getDayOfWeek() < DateTimeConstants.FRIDAY) {
d = d.withDayOfWeek(DateTimeConstants.FRIDAY));
} else {
d = d.plusWeeks(1).withDayOfWeek(DateTimeConstants.FRIDAY));
}
return d; // note that there's a possibility original object is returned
}
or even shorter
private LocalDate calcNextFriday(LocalDate d) {
if (d.getDayOfWeek() >= DateTimeConstants.FRIDAY) {
d = d.plusWeeks(1);
}
return d.withDayOfWeek(DateTimeConstants.FRIDAY);
}
private LocalDate calcNextFriday3(LocalDate d) {
return d.isBefore(d.dayOfWeek().setCopy(5))?d.dayOfWeek().setCopy(5):d.plusWeeks(1).dayOfWeek().setCopy(5);
}
Alternative approach
private LocalDate calcNextDay(LocalDate d, int weekday) {
return (d.getDayOfWeek() < weekday)?d.withDayOfWeek(weekday):d.plusWeeks(1).withDayOfWeek(weekday);
}
private LocalDate calcNextFriday2(LocalDate d) {
return calcNextDay(d,DateTimeConstants.FRIDAY);
}