How to get list of passed months of this year java?

Question

I am using SingleLine chart from PhilJay/MPAndroidChart android library and i need a list of passed months of current year. So for example from Jan to Oct, but when is October pass then from Jan to Nov and so on. I tried these: Getting List of Month for Past 1 year in Android dynamically, and Calculate previous 12 months from given month - SimpleDateFormat but all of these are for previosly 12 months and i want from start of current year

@SuppressLint("SimpleDateFormat")
private void handleXAxis() {
    List<String> allDates = new ArrayList<>();
    String maxDate = "Jan";
    SimpleDateFormat monthDate = new SimpleDateFormat("MMM");
    Calendar cal = Calendar.getInstance();
    try {
        cal.setTime(Objects.requireNonNull(monthDate.parse(maxDate)));
    } catch (ParseException e) {
        e.printStackTrace();
    }
    for (int i = 1; i <= 12; i++) {
        String month_name1 = monthDate.format(cal.getTime());
        allDates.add(month_name1);
        cal.add(Calendar.MONTH, -1);
    }
}

Get the month of the current date and then loop from 0 to month of current date - 1? — Joakim Danielson, Oct 06 '20 at 12:54
Why don't you use `java.time.YearMonth`? Looks like that's nearly all you need... Seriously, don't use `Calendar` or any other outdated class for this... — deHaar, Oct 06 '20 at 12:58

deHaar · Accepted Answer · 2020-10-07T07:12:10.717

tl;dr ⇒ `java.time`

Months until (including) the current one as List<YearMonth>:

public static List<YearMonth> getMonthsOfCurrentYear() {
    YearMonth currentMonth = YearMonth.now();
    List<YearMonth> yearMonths = new ArrayList<>();
    
    for (int month = 1; month <= currentMonth.getMonthValue(); month++) {
        yearMonths.add(YearMonth.of(currentMonth.getYear(), month));
    }
    
    return yearMonths;
}

Months until (including) the current one as List<String>:

public static List<String> getMonthNamesOfCurrentYear() {
    YearMonth currentMonth = YearMonth.now();
    List<String> yearMonths = new ArrayList<>();
    
    for (int month = 1; month <= currentMonth.getMonthValue(); month++) {
        yearMonths.add(YearMonth.of(currentMonth.getYear(), month)
                                .format(DateTimeFormatter.ofPattern("MMM",
                                                                    Locale.ENGLISH)));
    }
    
    return yearMonths;
}

as an alternative, you can use the display name of the Month instead of using a DateTimeFormatter.ofPattern("MMM")

public static List<String> getMonthNamesOfCurrentYear() {
    YearMonth currentMonth = YearMonth.now();
    List<String> yearMonths = new ArrayList<>();
    
    for (int month = 1; month <= currentMonth.getMonthValue(); month++) {
        yearMonths.add(Month.of(month)
                            .getDisplayName(TextStyle.SHORT, Locale.ENGLISH));
    }
    
    return yearMonths;
}

The output of the second and third example:

Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct

when invoked like

System.out.println(String.join(", ", getMonthNamesOfCurrentYear()));

How to get list of passed months of this year java?

1 Answers1

tl;dr ⇒ java.time

tl;dr ⇒ `java.time`