What happens when a static method is invoked using a null object reference?

Question

public class CallingStaticMethod {
public static void method() {
    System.out.println("I am in method");
}
public static void main(String[] args) {
    CallingStaticMethod csm = null;
    csm.method();
   }
}

Can someone explain how the static method is invoked in the above code?

Answer 1

It's been optimized away by the compiler, simply because having an instance of the class is not necessary. The compiler basically replaces

csm.method();

by

CallingStaticMethod.method();

It's in general also a good practice to do so yourself. Even the average IDE would warn you about accessing static methods through an instance, at least Eclipse does here.

Answer 2

Java allows you to use a Class instance to call static methods, but you should not confuse this allowance as if the method would be called on the instance used to call it.

instance.method();

is the same as

Class.method();