angry_cellophane

interface Common {
        void foo();
        void bar();
    }

    interface ConcreteWithSomething {
        void doSomething1();
        void doSomething2();
    }

    interface Concrete1 extends Common, ConcreteWithSomething {}

    interface Concrete2 extends ConcreteWithSomething {
        void doSomething3();
    }

    class Concrete2Impl implements Concrete2  {
        @Inject private Concrete1 delegate;

        public void doSomething1() { delegate.doSomething1(); }
        public void doSomething2() { delegate.doSomething2(); }
        public void doSomething3() {/*...*/}
    }