There is no need for an instance while invoking static member or method.
Since static members belongs to class rather than instance.
A null reference may be used to access a class (static) variable without causing an exception.
http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#d5e19846
If you see the example (see full example in spec)
public static void main(String[] args) {
System.out.println(favorite().mountain); //favorite() returns null
}
Even though the result of favorite() is null, a NullPointerException is not thrown. That "Mount " is printed demonstrates that the Primary expression is indeed fully evaluated at run time, despite the fact that only its type, not its value, is used to determine which field to access (because the field mountain is static).
