how to implement a static method in a class that implements an interface?

Question

I'm implementing a java class that implements an interface.
The poi is that, a method in this class must be static, but in the interface I can't (as known) declare a method as static, and if I try to declare it in the class, I get this error: "This static method cannot hide the instance method from InterfaceName".

I've searched in this site but I haven't found any solution but a suggestion said to create an abstract class that implements the interface, and then extend the abstract one in the class, but it doesn't work.

Any suggestion?

Thanks a lot to everybody!

do you have to override the static method? i don't think that is even allowed in java — Breavyn, Jul 31 '13 at 12:28
http://stackoverflow.com/questions/512877/why-cant-i-define-a-static-method-in-a-java-interface — mvw, Jul 31 '13 at 12:28
Hiding an instance method with a static method is confusing. Either remove the method from the interface or refrain from using the same name for your static method. — assylias, Jul 31 '13 at 12:35
so I can't have a static method in a class that implements an interface? — idell, Jul 31 '13 at 12:35
solved removing the method in the interface. thank's to everybody — idell, Jul 31 '13 at 12:38

score 4 · Accepted Answer · edited Feb 28 '18 at 17:48

The link mvw posted ( Why can't I define a static method in a Java interface? ) describes the reason for not allowing static methods in interfaces and why overriding static methods iis not a good idea (and thus not allowed).

It would be helpful to know in what situation you want to use the static method. If you just want to call a static method of the class, jut give it another name as andy256 suggested. If you want to call it from an object with a reference to the interface, do you really need the method to be static?

To get around the problem, my suggestion is that if you really want to call a static method with the same signature as the interface method, call a private static method:

class MyClass implememts SomeInterface {

    @Override
    public int someMethod(int arg1, int arg2) {
        return staticMethod(arg1, arg2);
    }

    private static int staticMethod(int arg1, int arg2) {
        // TODO: do some useful stuff...
        return arg1 + arg2;
    }
}

but in this way you can't use the method statically, MyClass.someMethod(1, 2) is not allowed. You need to have a instance of MyClass to call the someMethod. — Paul Marcelin Bejan, Nov 03 '22 at 12:28

how to implement a static method in a class that implements an interface?

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