如何获取任意年份的二月份有多少天?

如何获取任意年份的二月份有多少天?

import java.util.Calendar;
import java.util.Scanner;

public class CalendarDemo {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("请输入年份:");
int year = sc.nextInt();
Calendar c = Calendar.getInstance();
c.set(year, 2, 1);
c.add(Calendar.DATE,-1);
System.out.println(c.get(Calendar.DATE));
}
}