Age calculator

import javax.swing.JOptionPane;

public class AgeCalculation
{
    public static void main(String[] args)
    {

        String takeBirthDay = JOptionPane.showInputDialog("Enter Birthday(dd): ");
        String takeBirthMonth = JOptionPane.showInputDialog("Enter Birth Month(mm): ");
        String takeBirthYear = JOptionPane.showInputDialog("Enter Birth Year(yyyy): ");
        String takePresentDay = JOptionPane.showInputDialog("Enter Present day(dd): ");
        String takePresentMonth = JOptionPane.showInputDialog("Enter Present Month(mm): ");
        String takePresentYear = JOptionPane.showInputDialog("Enter Present Year(yyyy): ");

        int BirthDay = Integer.parseInt(takeBirthDay);
        int BirthMonth = Integer.parseInt(takeBirthMonth);
        int BirthYear = Integer.parseInt(takeBirthYear);
        int PresentDay = Integer.parseInt(takePresentDay);
        int PresentMonth = Integer.parseInt(takePresentMonth);
        int PresentYear = Integer.parseInt(takePresentYear);

        int month[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

        if (BirthDay > PresentDay)
        {
            PresentDay = PresentDay + month[BirthMonth - 1];
            PresentMonth = PresentMonth - 1;
        }

        if (BirthMonth > PresentMonth)
        {
            PresentYear = PresentYear - 1;
            PresentMonth = PresentMonth + 12;
        }

        int calculated_date = PresentDay - BirthDay;
        int calculated_month = PresentMonth - BirthMonth;
        int calculated_year = PresentYear - BirthYear;


        JOptionPane.showMessageDialog(null,"Your age is "+ calculated_date +" days, "+ calculated_month +" months and "+ calculated_year +" years.", "Result", JOptionPane.PLAIN_MESSAGE);
    }

}