### Question:
Quadruple extends Triple<R, S, T> implements Fourth<U>,
                   MappableFourth<U, Quadruple<R, S, T, ?>> { @Override public U getFourth() { return fourth; } Quadruple(R first, S second, T third, U fourth); static Quadruple<R, S, T, U> quadruple(R first, S second, T third, U fourth); @Override U getFourth(); @Override Quadruple<A, S, T, U> mapFirst(UnaryFunction<R, A> function); @Override Quadruple<R, A, T, U> mapSecond(UnaryFunction<S, A> function); @Override Quadruple<R, S, A, U> mapThird(UnaryFunction<T, A> function); @Override Quadruple<R, S, T, A> mapFourth(UnaryFunction<U, A> function); @Override Iterable<Object> getValues();  }### Answer:
@Test public void shouldReturnTheFourthObject() { Fourth<Double> quadruple = tuple(5, "Five", true, 3.6); Double fourth = quadruple.getFourth(); assertThat(fourth, is(3.6)); }