@Test
public void getsContentLanguage() throws Exception {

    MultivaluedMap<String, Object> headers = new MultivaluedHashMap<>();
    Locale locale = new Locale("en", "GB");
    headers.putSingle(CONTENT_LANGUAGE, locale);
    ResponseImpl response = new ResponseImpl(200, "foo", null, headers);
    assertSame(locale, response.getLanguage());
}