How can I generate age automatically when a date is selected from jdatechooser

Question

private void formWindowActivated(java.awt.event.WindowEvent evt) {    
    Date d = new Date();
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy");
    int YearNow = Integer.parseInt(sdf.format(d));
    int YearBD = Integer.parseInt(sdf.format(visitordob.getDate()));
    int Bd = YearNow - YearBD;
    jLabel.setText(Bd);
}

Answer 1

You can use LocalDate and Period.between(). Just remember to import them from java.time:

SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
Date date = formatter.parse(dob);
//Converting obtained Date object to LocalDate object
Instant instant = date.toInstant();
ZonedDateTime zone = instant.atZone(ZoneId.systemDefault());
LocalDate givenDate = zone.toLocalDate();
//Calculating the difference between given date to current date.
Period period = Period.between(givenDate, LocalDate.now());
System.out.print("Age: " + period.getYears());