First day of next month with java Joda-Time

java calendar jodatime
MatBanik picture MatBanik · Jan 24, 2011 · Viewed 40k times · Source

How would you rewrite the method below, which returns the first day of next month, with the org.joda.time package in Joda-Time?

public static Date firstDayOfNextMonth() {
    Calendar nowCal = Calendar.getInstance();
    int month = nowCal.get(Calendar.MONTH) + 1;
    int year = nowCal.get(Calendar.YEAR);

    Calendar cal = Calendar.getInstance();
    cal.clear();
    cal.set(Calendar.YEAR, year);
    cal.set(Calendar.MONTH, month);
    cal.set(Calendar.DAY_OF_MONTH, 1);
    Date dueDate = new Date(cal.getTimeInMillis());

    return dueDate;
}

Answer

leonbloy picture leonbloy · Jan 24, 2011 
   LocalDate today = new LocalDate();
   LocalDate d1 = today.plusMonths(1).withDayOfMonth(1);

A little easier and cleaner, isn't it? :-)

Update: If you want to return a date:

return new Date(d1.toDateTimeAtStartOfDay().getMillis());

but I strongly advise you to avoid mixing pure DATE types (i.e. a day in the calendar, without time information) with DATETIME types, specially with a "physical" datetime type as is the hideous java.util.Date . It's somewhat like converting from-to integer and floating types, you must be careful.

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