@Override
            public V as(T response) {
                requireNonNull(response, "response");
                return after.as(ResponseAs.this.as(response));
            }
Returns a composed {@link ResponseAs} that first applies this {@link ResponseAs} to
its input, and then applies the {@code after} {@link ResponseAs} to the result.
core/src/main/java/com/linecorp/armeria/client/ResponseAs.java