Age Calculator Difference in Kotlin [duplicate] - kotlin

Question

This question already has answers here:
How to create method for age calculation method in android
(7 answers)
Closed 4 months ago.
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 of 0 then how can solve this? Please help me to solve it.
My code is below:
public int getAge(int year, int month, int day) {
GregorianCalendar cal = new GregorianCalendar();
int y, m, d, noofyears;
y = cal.get(Calendar.YEAR);// current year ,
m = cal.get(Calendar.MONTH);// current month
d = cal.get(Calendar.DAY_OF_MONTH);// current day
cal.set(year, month, day);// here ur date
noofyears = (int) (y - cal.get(Calendar.YEAR));
LOGD("Age......", String.valueOf(noofyears));
if ((m < cal.get(Calendar.MONTH)) || ((m == cal.get(Calendar.MONTH)) && (d < cal.get(Calendar.DAY_OF_MONTH)))) {
--noofyears;
}
LOGD("Age......", String.valueOf(noofyears));
if (noofyears != 0) {
ageCount = noofyears;
} else {
ageCount = 0;
}
if (noofyears < 0)
throw new IllegalArgumentException("age < 0");
return noofyears;
}

Answer 1

java.time
For the sake of completeness and being up-to-date concerning packages, here is the way using java.time (Java 8+).
Java
public int getAge(int year, int month, int dayOfMonth) {
return Period.between(
LocalDate.of(year, month, dayOfMonth),
LocalDate.now()
).getYears();
}
Kotlin
fun getAge(year: Int, month: Int, dayOfMonth: Int): Int {
return Period.between(
LocalDate.of(year, month, dayOfMonth),
LocalDate.now()
).years
}
Both snippets need the following imports from java.time:
import java.time.LocalDate;
import java.time.Period
It's not recommended to use java.util.Date and java.util.Calendar anymore except from situations where you have to involve considerably large amounts of legacy code.
See also Oracle Tutorial.
For projects supporting Java 6 or 7, this functionality is available via the ThreeTenBP,
while there is special version, the ThreeTenABP for API levels below 26 in Android.
UPDATE
There's API Desugaring now in Android, which makes (a subset of) java.time directly available (no backport library needed anymore) to API levels below 26 (not really down to version 1, but will do for most of the API levels that should be supported nowadays).

Answer 2

private int getAge(String dobString){
Date date = null;
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
try {
date = sdf.parse(dobString);
} catch (ParseException e) {
e.printStackTrace();
}
if(date == null) return 0;
Calendar dob = Calendar.getInstance();
Calendar today = Calendar.getInstance();
dob.setTime(date);
int year = dob.get(Calendar.YEAR);
int month = dob.get(Calendar.MONTH);
int day = dob.get(Calendar.DAY_OF_MONTH);
dob.set(year, month+1, day);
int age = today.get(Calendar.YEAR) - dob.get(Calendar.YEAR);
if (today.get(Calendar.DAY_OF_YEAR) < dob.get(Calendar.DAY_OF_YEAR)){
age--;
}
return age;
}

Answer 3

Here is a Kotlin extension of the Date class returning the age corresponding to a Date object
val Date.age: Int
get() {
val calendar = Calendar.getInstance()
calendar.time = Date(time - Date().time)
return 1970 - (calendar.get(Calendar.YEAR) + 1)
}
It is compatible for all Android versions. If you wonder what '1970' is, that's the Unix Epoch. The timestamp is 0 on January 1, 1970.

Answer 4

private boolean getAge(int year, int month, int day) {
try {
Calendar dob = Calendar.getInstance();
Calendar today = Calendar.getInstance();
dob.set(year, month, day);
int monthToday = today.get(Calendar.MONTH) + 1;
int monthDOB = dob.get(Calendar.MONTH)+1;
int age = today.get(Calendar.YEAR) - dob.get(Calendar.YEAR);
if (age > 18) {
return true;
} else if (age == 18) {
if (monthDOB > monthToday) {
return true;
} else if (monthDOB == monthToday) {
int todayDate = today.get(Calendar.DAY_OF_MONTH);
int dobDate = dob.get(Calendar.DAY_OF_MONTH);
if (dobDate <= todayDate) { // should be less then
return true;
} else {
return false;
}
} else {
return false;
}
} else {
return false;
}
} catch (Exception e) {
e.printStackTrace();
}
return false;
}

Answer 5

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

Answer 6

Now for kotlin Language:
import java.util.Calendar
fun main(args: Array<String>) {
print(getAge(yyyy,mm,dd))
}
fun getAge(year: Int, month: Int, day: Int): String {
val dob = Calendar.getInstance()
val today = Calendar.getInstance()
dob.set(year, month, day)
var age = today.get(Calendar.YEAR) - dob.get(Calendar.YEAR)
if (today.get(Calendar.DAY_OF_YEAR) < dob.get(Calendar.DAY_OF_YEAR)) {
age--
}
val ageInt = age + 1
return ageInt.toString()
}

Answer 7

private void calculateAge() {
age.calcualteYear();
age.calcualteMonth();
age.calcualteDay();
age.calculateMonths();
age.calTotalWeeks();
age.calTotalHours();
age.calTotalMins();
age.calTotalSecs();
age.calTotalMilsecs();
// Toast.makeText(getContext(), "click the resulted button"+age.getResult() , Toast.LENGTH_SHORT).show();
result.setText("AGE (DD/MM/YY) :" + age.getResult());
}
after that create one class
public class AgeCalculation {
private int startYear;
private int startMonth;
private int startDay;
private int endYear;
private int endMonth;
private int endDay;
private int resYear;
private int resMonth;
private int resDay;
private Calendar start;
private Calendar end;
public String getCurrentDate()
{
end=Calendar.getInstance();
endYear=end.get(Calendar.YEAR);
endMonth=end.get(Calendar.MONTH);
endMonth++;
endDay=end.get(Calendar.DAY_OF_MONTH);
return endDay+":"+endMonth+":"+endYear;
}
public void setDateOfBirth(int sYear, int sMonth, int sDay)
{
startYear=sYear;
startMonth=sMonth;
startDay=sDay;
}
public void calcualteYear()
{
resYear=endYear-startYear/(365);
}
public void calcualteMonth()
{
if(endMonth>=startMonth)
{
resMonth= endMonth-startMonth;
}
else
{
resMonth=endMonth-startMonth;
resMonth=12+resMonth;
resYear--;
}
}
public void calcualteDay()
{
if(endDay>=startDay)
{
resDay= endDay-startDay;
}
else
{
resDay=endDay-startDay;
resDay=30+resDay;
if(resMonth==0)
{
resMonth=11;
resYear--;
}
else
{
resMonth--;
}
}
}
public String getResult()
{
return resDay+":"+resMonth+":"+resYear;
}

Answer 8

public String getAge(int year, int month, int day) {
Calendar dob = Calendar.getInstance();
Calendar today = Calendar.getInstance();
dob.set(year, month-1, day);
int age = today.get(Calendar.YEAR) - dob.get(Calendar.YEAR);
if (today.get(Calendar.DAY_OF_YEAR) < dob.get(Calendar.DAY_OF_YEAR)) {
age--;
}
Integer ageInt = new Integer(age);
String ageS = ageInt.toString();
return ageS;
}

Answer 9

static int calculateAge(int birthdayDay, int birthdayMonth, int birthdayYear)
{
DateTime date = DateTime(birthdayYear, birthdayMonth, birthdayDay).toLocal();
DateTime now = DateTime.now().toLocal();
return now.difference(date).inDays ~/ 365.2425;
}

Answer 10

public int getAge(int year, int month, int day) {
final Calendar birthDay = Calendar.getInstance();
birthDay.set(year, month, day);
final Calendar current = Calendar.getInstance();
if (current.getTimeInMillis() < birthDay.getTimeInMillis())
throw new IllegalArgumentException("age < 0");
int age = current.get(Calendar.YEAR) - birthDay.get(Calendar.YEAR);
if (birthDay.get(Calendar.MONTH) > current.get(Calendar.MONTH) ||
(birthDay.get(Calendar.MONTH) == current.get(Calendar.MONTH) &&
birthDay.get(Calendar.DATE) > current.get(Calendar.DATE)))
age--;
return age;
}

Answer 11

This is how I implement in my source code, I tested. Hope that it is useful :
public static int getAge(String dateTime, String currentFormat) {
SimpleDateFormat dateFormat = new SimpleDateFormat(currentFormat);
try {
Date date = dateFormat.parse(dateTime);
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
int year = calendar.get(Calendar.YEAR);
int month = calendar.get(Calendar.MONTH);
int day = calendar.get(Calendar.DAY_OF_MONTH);
Date currentDate = new Date();
Calendar currentCalendar = Calendar.getInstance();
currentCalendar.setTime(currentDate);
int currentYear = currentCalendar.get(Calendar.YEAR);
int currentMonth = currentCalendar.get(Calendar.MONTH);
int currentDay = currentCalendar.get(Calendar.DAY_OF_MONTH);
int deltaYear = currentYear - year;
int deltaMonth = currentMonth - month;
int deltaDay = currentDay - day;
if (deltaYear > 0) {
if (deltaMonth < 0) {
deltaYear --;
} else if (deltaDay < 0){
deltaYear --;
}
return deltaYear;
}
} catch (java.text.ParseException e) {
e.printStackTrace();
}
return 0;
}

Answer 12

String getAgeInOther(int year, int month, int day) {
Calendar today = Calendar.getInstance();
Calendar birth = Calendar.getInstance();
birth.set(year, month, day);
Calendar temp = Calendar.getInstance();
temp.set(year, month, day);
int totalDays = 0;
int intMonth=0,intDays=0;
for (int iYear = birth.get(Calendar.YEAR); iYear <= today.get(Calendar.YEAR); iYear++) {
if (iYear == today.get(Calendar.YEAR) && iYear == birth.get(Calendar.YEAR)) {
for (int iMonth = birth.get(Calendar.MONTH); iMonth <= today.get(Calendar.MONTH); iMonth++) {
temp.set(iYear, iMonth, 1);
if ((iMonth == today.get(Calendar.MONTH)) && (iMonth == birth.get(Calendar.MONTH))) {
totalDays += today.get(Calendar.DAY_OF_MONTH) - birth.get(Calendar.DAY_OF_MONTH);
} else if ((iMonth != today.get(Calendar.MONTH)) && (iMonth != birth.get(Calendar.MONTH))) {
totalDays += temp.getActualMaximum(Calendar.DAY_OF_MONTH);
intMonth++;
}else if ((iMonth == birth.get(Calendar.MONTH))) {
totalDays +=( birth.getActualMaximum(Calendar.DAY_OF_MONTH)- birth.get(Calendar.DAY_OF_MONTH));
} else if ((iMonth == today.get(Calendar.MONTH))){
totalDays += today.get(Calendar.DAY_OF_MONTH);
if (birth.get(Calendar.DAY_OF_MONTH)<today.get(Calendar.DAY_OF_MONTH))
{
intMonth++;
intDays=today.get(Calendar.DAY_OF_MONTH)-birth.get(Calendar.DAY_OF_MONTH);
}else {
temp.set(today.get(Calendar.YEAR),today.get(Calendar.MONTH)-1,1);
intDays=temp.getActualMaximum(Calendar.DAY_OF_MONTH)-birth.get(Calendar.DAY_OF_MONTH)+today.get(Calendar.DAY_OF_MONTH);
}
}
}
} else if ((iYear != today.get(Calendar.YEAR)) && (iYear != birth.get(Calendar.YEAR))) {
for (int iMonth = 0; iMonth < 12; iMonth++) {
temp.set(iYear, iMonth, 1);
totalDays += temp.getActualMaximum(Calendar.DAY_OF_MONTH);
intMonth++;
}
} else if (((iYear) == birth.get(Calendar.YEAR))) {
for (int iMonth = birth.get(Calendar.MONTH); iMonth < 12; iMonth++) {
temp.set(iYear, iMonth, 1);
if ((iMonth == birth.get(Calendar.MONTH))) {
totalDays += (birth.getActualMaximum(Calendar.DAY_OF_MONTH)-birth.get(Calendar.DAY_OF_MONTH));
} else {
intMonth++;
totalDays += temp.getActualMaximum(Calendar.DAY_OF_MONTH);
}
}
} else if (iYear == today.get(Calendar.YEAR)) {
for (int iMonth = 0; iMonth <= today.get(Calendar.MONTH); iMonth++) {
temp.set(iYear, iMonth, 1);
if ((iMonth == today.get(Calendar.MONTH))) {
totalDays += today.get(Calendar.DAY_OF_MONTH);
if (birth.get(Calendar.DAY_OF_MONTH)<today.get(Calendar.DAY_OF_MONTH))
{
intMonth++;
intDays=today.get(Calendar.DAY_OF_MONTH)-birth.get(Calendar.DAY_OF_MONTH);
}else {
temp.set(today.get(Calendar.YEAR),today.get(Calendar.MONTH)-1,1);
intDays=temp.getActualMaximum(Calendar.DAY_OF_MONTH)-birth.get(Calendar.DAY_OF_MONTH)+today.get(Calendar.DAY_OF_MONTH);
}
} else {
intMonth++;
totalDays += temp.getActualMaximum(Calendar.DAY_OF_MONTH);
}
}
}
}
int ageYear=intMonth/12;
int ageMonth=intMonth%12;
int ageDays=intDays;
//TODO if you want age in YEAR:MONTH:DAY REMOVE COMMENTS
//TODO return ageYear+":"+ageMonth+":"+ageDays;
return ""+totalDays;//todo TOTAL AGE IN DAYS
}

Answer 13

public static String calculateAge(String strDate) {
int years = 0;
int months = 0;
int days = 0;
try {
long timeInMillis = Long.parseLong(strDate);
Date birthDate = new Date(timeInMillis);
//create calendar object for birth day
Calendar birthDay = Calendar.getInstance();
birthDay.setTimeInMillis(birthDate.getTime());
//create calendar object for current day
long currentTime = System.currentTimeMillis();
Calendar now = Calendar.getInstance();
now.setTimeInMillis(currentTime);
//Get difference between years
years = now.get(Calendar.YEAR) - birthDay.get(Calendar.YEAR);
int currMonth = now.get(Calendar.MONTH) + 1;
int birthMonth = birthDay.get(Calendar.MONTH) + 1;
//Get difference between months
months = currMonth - birthMonth;
//if month difference is in negative then reduce years by one and calculate the number of months.
if (months < 0) {
years--;
months = 12 - birthMonth + currMonth;
if (now.get(Calendar.DATE) < birthDay.get(Calendar.DATE))
months--;
} else if (months == 0 && now.get(Calendar.DATE) < birthDay.get(Calendar.DATE)) {
years--;
months = 11;
}
//Calculate the days
if (now.get(Calendar.DATE) > birthDay.get(Calendar.DATE))
days = now.get(Calendar.DATE) - birthDay.get(Calendar.DATE);
else if (now.get(Calendar.DATE) < birthDay.get(Calendar.DATE)) {
int today = now.get(Calendar.DAY_OF_MONTH);
now.add(Calendar.MONTH, -1);
days = now.getActualMaximum(Calendar.DAY_OF_MONTH) - birthDay.get(Calendar.DAY_OF_MONTH) + today;
} else {
days = 0;
if (months == 12) {
years++;
months = 0;
}
}
//adarsh
if (currMonth > birthMonth) {
if (birthDay.get(Calendar.DATE) > now.get(Calendar.DATE)) {
months = months - 1;
}
}//---------------------------------
} catch (Exception e) {
e.printStackTrace();
}
//Create new Age object
return years + " Y " + months + " M " + days + " days";
}

Answer 14

Here is my solution in Kotlin:
import java.time.LocalDateTime
fun getAge(birthYear: Int, birthMonth: Int, birthDay: Int): Int {
var age: Int = LocalDateTime.now().year - birthYear
if (birthMonth > LocalDateTime.now().monthValue || birthMonth == LocalDateTime.now().monthValue && birthDay > LocalDateTime.now().dayOfMonth) { age-- }
if (age < 0) { age = 0 }
return age
}

Answer 15

int age =0;
age = yearLatest - yearBirth;
if (monthAge > currentMonth) {
if (age != 0) {
age = age - 1;
}
} else if(monthAge == currentMonth){
if (dayAge > currentDay) {
if (age != 0) {
age = age - 1;
}
}
}
return age;

Answer 16

If we want to directly check if age is below or above X age then we can use LocalDate type, work for all the Android API levels.
LocalDate.now().minusYears(18).isBefore(value) //value is your localDate

Answer 17

This is the shortest I could get it to.
static int calculateAge(Calendar birthDay){
Calendar today = Calendar.getInstance();
int age = today.get(Calendar.YEAR) - birthDay.get(Calendar.YEAR);
if (birthDay.get(Calendar.DAY_OF_YEAR) < today.get(Calendar.DAY_OF_YEAR)) {
age--;
}
return age;
}

Answer 18

New Language Dart using DateTime
static int getPerfectAgeInYears(DateTime dob,DateTime today) {
dob = DateTime(dob.year,dob.month,dob.day);
int ageInteger = 0;
today = DateTime(today.year,today.month,today.day);
ageInteger = today.year-dob.year;
if (today.month == dob.month) {
if (today.day < dob.day) {
ageInteger = ageInteger - 1;
}
} else if (today.month < dob.month) {
ageInteger = ageInteger - 1;
}
return ageInteger;}
Call as print(getPerfectAgeInYears(DateTime(2000,6,4),DateTime.now()));
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