### Question:
BasicHttpRequest implements HttpRequest { @Override public HttpHeaders headers() { return this.headers; } BasicHttpRequest(URI uri, String method, Map<String, List<String>> headers); @Override URI uri(); @Override String method(); @Override HttpHeaders headers(); @Override HttpQueryParams parseQuery();  }### Answer:
@Test public void testHeaderAllValues() { assertThat(request.headers().allValues("accept"), hasItems("text/plain", "application/json")); }