@Test public void accessControlAllowHeaders() { List<String> allowedHeaders = headers.getAccessControlAllowHeaders(); assertThat(allowedHeaders, Matchers.emptyCollectionOf(String.class)); headers.setAccessControlAllowHeaders(Arrays.asList("header1", "header2")); allowedHeaders = headers.getAccessControlAllowHeaders(); assertEquals(allowedHeaders, Arrays.asList("header1", "header2")); }