@Override
    public DiscreteResource child(Object child) {
        checkArgument(!(child instanceof Class<?>));

        return Resources.discrete(id.child(child)).resource();
    }
@Test
    public void testChild() {
        DiscreteResource r1 = Resources.discrete(D1).resource().child(P1);
        DiscreteResource sameAsR2 = Resources.discrete(D1, P1).resource();

        assertThat(r1, is(sameAsR2));
    }