Age

import java.util.Calendar;
import java.util.GregorianCalendar;

public class Age {
  public static void main(String[] args) {
    int birth_year = 1990, birth_month = 4, birth_day = 25;
    Calendar birth = new GregorianCalendar(birth_year, birth_month - 1, birth_day);
    Calendar today = new GregorianCalendar();
    int age = today.get(Calendar.YEAR) - birth_year;
    if (today.get(Calendar.MONTH) == birth_month && today.get(Calendar.DAY_OF_MONTH) < birth_day)
      age--;
    else if (today.get(Calendar.MONTH) < birth_month)
      age--;
    System.out.format("%tY年%tm月%td日生まれ\n", birth, birth, birth);
    System.out.format("%d歳です。（%tY年%tm月%td日現在）\n", age, today, today, today);
  }
}