Get the last day of a month

import java.util.GregorianCalendar;
import java.util.Calendar;
import java.text.DateFormat;

public class DateUtils {

  public static String getLastDay(String year, String month) {

    GregorianCalendar calendar = new GregorianCalendar();

    int yearInt = Integer.parseInt(year);
    int monthInt = Integer.parseInt(month);

    monthInt = monthInt - 1;

    calendar.set(yearInt, monthInt, 1);

    int dayInt = calendar.getActualMaximum(GregorianCalendar.DAY_OF_MONTH);

    return Integer.toString(dayInt);
  }

}