public static <T extends Serializable> CacheableOptional<T> of(final T value) {
        return new CacheableOptional<>(value);
    }
@Test
    public void equalsIsAppropriate() {

        assertThat(CacheableOptional.of("my-test"), is(CacheableOptional.of("my-test")));
        assertThat(CacheableOptional.of("my-test"), is(not(CacheableOptional.of("not-my-test"))));

    }