I need to get the dates of last two Fridays using today's date.This is the code I'm currently using public class GetDate {
public static void main(String[] args) {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date dt = new Date();
Calendar c = Calendar.getInstance();
c.setTime(dt);
System.out.println("today : " + sdf.format(dt));
while (c.get(Calendar.DAY_OF_WEEK) != 6) {
c.add(Calendar.DATE, -1);
}
Date lastFri=c.getTime();
System.out.println("last fri : "+sdf.format(lastFri));
c.add(Calendar.DATE, -7);
Date prevFri = c.getTime();
System.out.println("previous friday : "+sdf.format(prevFri));
}
}
Is there any way to optimize this code??
With Java 8, and if you don't have to use the Calendar api, you can use a TemporalAdjuster
:
LocalDate today = LocalDate.now();
LocalDate prevFriday = today.with(previous(FRIDAY));
LocalDate prevPrevFriday = prevFriday.with(previous(FRIDAY));
note: requires the following static import
import static java.time.temporal.TemporalAdjusters.previous;
import static java.time.DayOfWeek.FRIDAY;
You could get the last Friday this way :
Calendar cal = Calendar.getInstance();
cal.add(Calendar.WEEK_OF_YEAR, -1);
cal.set(Calendar.DAY_OF_WEEK, Calendar.FRIDAY);
This gets the last Friday by subtracting a week and setting the day of week to Friday.
Try something like:
cal.add(Calendar.WEEK_OF_YEAR, -1);
cal.set(Calendar.DAY_OF_WEEK, Calendar.FRIDAY);
Date lastFriday = cal.getTime();
cal.add(Calendar.WEEK_OF_YEAR, -1);
cal.set(Calendar.DAY_OF_WEEK, Calendar.FRIDAY);
Date lastToLastFriday = cal.getTime();
This line should help:
calendar.add(Calendar.DATE, Calendar.FRIDAY - 7 - c.get(Calendar.DAY_OF_WEEK));
So this code is solving your problem:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar c = GregorianCalendar.getInstance();
c.add(Calendar.DATE, Calendar.FRIDAY - 7 - c.get(Calendar.DAY_OF_WEEK));
System.out.println(sdf.formate(c.getTime()));
c.add(Calendar.DATE, Calendar.FRIDAY - 14 - c.get(Calendar.DAY_OF_WEEK));
System.out.println(sdf.formate(c.getTime()));
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