JAVA 一个月多少天

从0开始，0代表一月

public class TheMonthOfTheLastDay {

    public static void main(String[] args) {
        TheMonthOfTheLastDay themonthofthelastday = new TheMonthOfTheLastDay();
        System.out.println(getLastDayOfMonth(2102,7));
    }
    public static int getLastDayOfMonth(int year, int month) {     
         Calendar cal = Calendar.getInstance();     
         cal.set(Calendar.YEAR, year);     
         cal.set(Calendar.MONTH, month);     
         //cal.set(Calendar.DAY_OF_MONTH,cal.getActualMaximum(Calendar.DATE));  
         //System.out.println(cal.DAY_OF_MONTH);
         //System.out.println(cal.getActualMaximum(Calendar.DATE));
         //System.out.println(cal.getActualMinimum(Calendar.DATE));
        //return  new   SimpleDateFormat( "yyyy-MM-dd ").format(cal.getTime());  
        return cal.getActualMaximum(Calendar.DATE);
        
     }   

}