How do I calculate someone's age in Java?

Question

I want to return an age in years as an int in a Java method. What I have now is the following where getBirthDate() returns a Date object (with the birth date ;-)):

Answer 1

public class CalculateAge { 

private int age;

private void setAge(int age){

    this.age=age;

}
public void calculateAge(Date date){

    Calendar calendar=Calendar.getInstance();

    Calendar calendarnow=Calendar.getInstance();    

    calendarnow.getTimeZone();

    calendar.setTime(date);

    int getmonth= calendar.get(calendar.MONTH);

    int getyears= calendar.get(calendar.YEAR);

    int currentmonth= calendarnow.get(calendarnow.MONTH);

    int currentyear= calendarnow.get(calendarnow.YEAR);

    int age = ((currentyear*12+currentmonth)-(getyears*12+getmonth))/12;

    setAge(age);
}
public int getAge(){

    return this.age;

}