public interface Ibase1 {

    public void method1();

}


public interface Isub {

    public void method2();

}


public interface Isub2 extends Ibase1, Isub {

    public void method3();

}


public class Test implements Isub2 {

    public void method1() {

        System.out.println("hello!");

    }

    public void method2() {

        System.out.println("hello!");

    }

    public void method3() {

        System.out.println("hello!");

    }

}


public class Main {

    public static void main(String[] args) {

        Test i = new Test();

        Ibase1 ia = i;

        i.method1();

    }

}