Calculate age from BirthDate

Question

I have DatePicker Dialog, When I select date at that time I want to calculate age it\'s working but when I select date of current year at that time it showing the -1 age instead

Answer 1

public static int getPerfectAgeInYears(int year, int month, int date) {

    Calendar dobCalendar = Calendar.getInstance();
    
    dobCalendar.set(Calendar.YEAR, year);
    dobCalendar.set(Calendar.MONTH, month);
    dobCalendar.set(Calendar.DATE, date);

    int ageInteger = 0;

    Calendar today = Calendar.getInstance();

    ageInteger = today.get(Calendar.YEAR) - dobCalendar.get(Calendar.YEAR);

    if (today.get(Calendar.MONTH) == dobCalendar.get(Calendar.MONTH)) {

        if (today.get(Calendar.DAY_OF_MONTH) < dobCalendar.get(Calendar.DAY_OF_MONTH)) {

            ageInteger = ageInteger - 1;
        }

    } else if (today.get(Calendar.MONTH) < dobCalendar.get(Calendar.MONTH)) {

        ageInteger = ageInteger - 1;

    }

    return ageInteger;
}

Consider Today's Date - 30th August 2020

If Birthdate - 29th July 1993, the output - 27

If Birthdate - 29th August 1993, the output - 27

If Birthdate - 30th August 1993, the output - 27

If Birthdate - 31st August 1993, the output - 26

If Birthdate - 31st September 1993, the output - 26