import java.time.DayOfWeek;
import java.time.LocalDate;
import java.time.YearMonth;
import java.time.temporal.TemporalAdjusters;
import java.util.List;
import java.util.stream.Collectors;
 
public class Main {
	public static void main(String[] args) {
		// Test
		System.out.println(getWeekends(2));// All weekends of Feb in the current year
		System.out.println(getWeekends(2020, 2));// All weekends of Feb 2020
	}
 
	/*
	 * All weekends (Sat & Sun) of the given month in the current year
	 */
	static List<LocalDate> getWeekends(int month) {
		LocalDate firstDateOfTheMonth = LocalDate.now().withMonth(month).with(TemporalAdjusters.firstDayOfMonth());
 
		return firstDateOfTheMonth
				.datesUntil(firstDateOfTheMonth.plusMonths(1))
				.filter(date -> date.getDayOfWeek() == DayOfWeek.SATURDAY || date.getDayOfWeek() == DayOfWeek.SUNDAY)
				.collect(Collectors.toList());
	}
 
	/*
	 * All weekends (Sat & Sun) of the given year and the month
	 */
	static List<LocalDate> getWeekends(int year, int month) {
		LocalDate firstDateOfTheMonth = YearMonth.of(year, month).atDay(1);
 
		return firstDateOfTheMonth
				.datesUntil(firstDateOfTheMonth.plusMonths(1))
				.filter(date -> date.getDayOfWeek() == DayOfWeek.SATURDAY || date.getDayOfWeek() == DayOfWeek.SUNDAY)
				.collect(Collectors.toList());
	}
}

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