Why can't I define a static method in a Java interface?

Question

EDIT: As of Java 8, static methods are now allowed in interfaces.

Here\'s the example:

public interface IXMLizable         


        

Answer 1

With the advent of Java 8 it is possible now to write default and static methods in interface. docs.oracle/staticMethod

For example:

public interface Arithmetic {

    public int add(int a, int b);

    public static int multiply(int a, int b) {
        return a * b;
    }
}

public class ArithmaticImplementation implements Arithmetic {

    @Override
    public int add(int a, int b) {
        return a + b;
    }

    public static void main(String[] args) {
        int result = Arithmetic.multiply(2, 3);
        System.out.println(result);
    }
}

Result : 6

TIP : Calling an static interface method doesn't require to be implemented by any class. Surely, this happens because the same rules for static methods in superclasses applies for static methods on interfaces.