Calling last Friday in November every year

Question

I have a code that manually calls the last Friday of the month for the year 2020. It is necessary for the code to recognize and call the last Friday in the month of November every year, can anyone help, thank you.

    Calendar lastday = Calendar.getInstance();
    int month = lastday.get(Calendar.MONTH);
    int dayOfMonth = lastday.get(Calendar.DAY_OF_MONTH);
    if(month == Calendar.NOVEMBER && dayOfMonth == 27){
        .....
    }

score 1 · Accepted Answer · answered Nov 12 '20 at 09:39

1

your answer:

Calendar lastday = Calendar.getInstance();
int month = lastday.get(Calendar.MONTH);
int dayOfMonth = lastday.get(Calendar.DAY_OF_MONTH);
int day = lastday.get(Calendar.DAY_OF_WEEK); 
if(month == Calendar.NOVEMBER && dayOfMonth >= 24 && day == Calendar.FRIDAY){
    .....
}

answered Nov 12 '20 at 09:39

Ali Najafi

118
1
3

Congratulations on your logic, you have a great idea that the last Friday in November cannot be less than 24 days! Praise! – Cule Nov 12 '20 at 10:05
@Cule Thank you , this is first answer in stackoverflow.com! – Ali Najafi Nov 12 '20 at 10:19
`@Ali Najafi` Bravo, I'm delighted with your logic! – Cule Nov 12 '20 at 12:54

Natig Babayev · Answer 2 · 2020-11-12T09:52:25.400

You can use following solution. By changing calendar.set(Calendar.MONTH, Calendar.NOVEMBER), it should be usable for any month:

public int getLastFridayOfNovember() {
    Calendar calendar = Calendar.getInstance();
    calendar.set(Calendar.MONTH, Calendar.NOVEMBER);

    int totalDaysInMonth = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
    calendar.set(Calendar.DAY_OF_MONTH, totalDaysInMonth);

    int daysToRollBack = (calendar.get(Calendar.DAY_OF_WEEK) + 1) % 7;
    return totalDaysInMonth - daysToRollBack;
}

Usage is simple:

...
int lastDayOfNovember = getLastFridayOfNovember();

If you use Kotlin, it can be extension function as well:

fun Calendar.getLastFridayOfMonth(): Int {
    val totalDaysInMonth = getActualMaximum(Calendar.DAY_OF_MONTH)
    this[Calendar.DAY_OF_MONTH] = totalDaysInMonth
    val daysToRollBack = (this[Calendar.DAY_OF_WEEK] + 1) % 7
    return totalDaysInMonth - daysToRollBack
}

Usage:

val calendar = Calendar.getInstance()
// set month
calendar.set(Calendar.MONTH, Calendar.NOVEMBER);
// get last Friday of given month
val lastFridayOfNovember = calendar.getLastFridayOfMonth()

`@Natig Babayev` Thanks for your solution. – Cule Nov 12 '20 at 17:26 — Cule, Nov 12 '20 at 17:26

Ole V.V. · Answer 3 · 2020-11-12T19:16:56.457

java.time either through desugaring or through ThreeTenABP

Always consider using java.time, the modern Java date and time API, for your date work. And even more so for queries that are a bit more complex like yours here.

    LocalDate today = LocalDate.now(ZoneId.systemDefault());
    boolean isLastFridayOfNovember = today.getMonth().equals(Month.NOVEMBER)
            && today.equals(today.with(TemporalAdjusters.lastInMonth(DayOfWeek.FRIDAY)));
    System.out.println("Is it the last Friday in November? " + isLastFridayOfNovember);

Output when I ran today (Thursday November 12):

Is it the last Friday in November? false

The expression today.with(TemporalAdjusters.lastInMonth(DayOfWeek.FRIDAY)) calculates the last Friday of the current month. If today is equal to the calculated date and we are in November, then we’re on the last Friday of November.

To calculate the last Friday in November for a given year:

    int year = 2021;
    LocalDate lastFridayInNovember = LocalDate.of(year, Month.NOVEMBER, 30)
            .with(TemporalAdjusters.previousOrSame(DayOfWeek.FRIDAY));
    
    System.out.println(lastFridayInNovember);

2021-11-26

Question: Doesn’t java.time require Android API level 26?

java.time works nicely on both older and newer Android devices. It just requires at least Java 6.

In Java 8 and later and on newer Android devices (from API level 26) the modern API comes built-in.
In non-Android Java 6 and 7 get the ThreeTen Backport, the backport of the modern classes (ThreeTen for JSR 310; see the links at the bottom).
On older Android either use desugaring or the Android edition of ThreeTen Backport. It’s called ThreeTenABP. In the latter case make sure you import the date and time classes from org.threeten.bp with subpackages.

Links

Oracle tutorial: Date Time explaining how to use java.time.
Java Specification Request (JSR) 310, where java.time was first described.
ThreeTen Backport project, the backport of java.time to Java 6 and 7 (ThreeTen for JSR-310).
Java 8+ APIs available through desugaring
ThreeTenABP, Android edition of ThreeTen Backport
Question: How to use ThreeTenABP in Android Project, with a very thorough explanation.

Calling last Friday in November every year

3 Answers3

java.time either through desugaring or through ThreeTenABP

Question: Doesn’t java.time require Android API level 26?

Links