// enums actually inherit from  Enum
public enum Month {
    // elements of enum are really subclasses
    JANUARY(31),
    
    FEBRUARY(28) {
        // can override methods from enum
        // february's days depend on leap year
        public int getDays() {
            // using static var of enum
            if (leapyear) {
                return days + 1;
            }
            // calling overridden method
            return super.getDays();
        }
    },
    MARCH(31),
    APRIL(30),
    MAY(31),
    JUNE(30),
    JULY(31),
    AUGUST(31),
    SEPTEMBER(30),
    OCTOBER(31),
    NOVEMBER(30),
    DECEMBER(31);
    

    protected final int days;
    
    Month(int d) {
        days = d;
    }    
    
    public int getDays() {
        return days;
    }
    
    public String toString() {
        // class Enum has a toString
        return super.toString() + " is a month with " + getDays() + " days.";
    }
    
    // enums can have statics too
    private static boolean leapyear;
    
    public static boolean getLeapyear() {
        return leapyear;
    }
    
    public static void setLeapYear(boolean b) {
        leapyear = b;
    }
    
    
}