ResourceOptions { public ResourceOptions group(String group) { FeatureException.throwIfNullOrEmpty(group, "Please provide a group"); this.group = group; return this; }  ResourceOptions securityTokenProvider(AuthorizationProvider provider); ResourceOptions header(String name, Object value); ResourceOptions headers(Map<String, Object> headers); ResourceOptions scope(String scope); ResourceOptions group(String group); Map<String, Object> headers(); Optional<Authorization> supplyToken(); String scope(); String group();  }
@Test public void testGroup() { ResourceOptions ro = new ResourceOptions(); try { ro.group(null); fail(); } catch (Exception ignored) { } try { ro.group(""); fail(); } catch (Exception ignored) { } assertEquals("grp", ro.group("grp").group()); }