Why should the static field be accessed in a static way?

java static
Ava picture Ava · Apr 13, 2011 · Viewed 105.6k times · Source 
public enum MyUnits
{
    MILLSECONDS(1, "milliseconds"), SECONDS(2, "seconds"),MINUTES(3,"minutes"), HOURS(4, "hours");

    private MyUnits(int quantity, String units)
    {
        this.quantity = quantity;
        this.units = units;
    }

    private int quantity;
    private  String units;

 public String toString() 
 {
    return (quantity + " " + units);
 }

 public static void main(String[] args) 
 {
    for (MyUnits m : MyUnits.values())
    {
        System.out.println(m.MILLSECONDS);
        System.out.println(m.SECONDS);
        System.out.println(m.MINUTES);
        System.out.println(m.HOURS);
    }
 }
}

This is referring to post ..wasnt able to reply or comment to any so created a new one. Why are my 

System.out.println(m.MILLSECONDS);

giving warnings-The static field MyUnits.MILLSECONDS should be accessed in a static way ? Thanks.

Answer

Chris Thompson picture Chris Thompson · Apr 13, 2011

Because when you access a static field, you should do so on the class (or in this case the enum). As in

MyUnits.MILLISECONDS;

Not on an instance as in

m.MILLISECONDS;

Edit To address the question of why: In Java, when you declare something as static, you are saying that it is a member of the class, not the object (hence why there is only one). Therefore it doesn't make sense to access it on the object, because that particular data member is associated with the class.

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