Javaで特定の年の特定の月の日数を確認するにはどうすればよいですか?

public int getActualMaximum(int field)

import java.util.*;
public class NoOfDaysInAMonthOfAYearTest {
   public static void main(String []args) {
      for (int i = 2000; i < 2018; i++) {
         Calendar calendar = new GregorianCalendar(i, Calendar.FEBRUARY, 1);
         int numberOfDays = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
         System.out.println("February " + i + ": " + numberOfDays + " days");
      }
   }
}

February 2000: 29 days
February 2001: 28 days
February 2002: 28 days
February 2003: 28 days
February 2004: 29 days
February 2005: 28 days
February 2006: 28 days
February 2007: 28 days
February 2008: 29 days
February 2009: 28 days
February 2010: 28 days
February 2011: 28 days
February 2012: 29 days
February 2013: 28 days
February 2014: 28 days
February 2015: 28 days
February 2016: 29 days
February 2017: 28 days