### Question:
ResourceLoaderUtils { public static String formatDateHeader(long value) { Instant instant = Instant.ofEpochMilli(value); ZonedDateTime zdt = ZonedDateTime.ofInstant(instant, HTTP_RESPONSE_DATE_HEADER.getZone()); return HTTP_RESPONSE_DATE_HEADER.format(zdt); }  static String formatDateHeader(long value); static Long parseDateHeader(String value); static long getResourceLastModified(URL url); static long getResourceLastModified(URLConnection connection); static int getDepth(String path); static boolean isDirectory(String path);  }### Answer:
@Test public void testFormatDateHeader() { Assert.assertEquals("Tue, 16 Jul 2019 08:10:19 GMT", ResourceLoaderUtils.formatDateHeader(1563264619000L)); Assert.assertEquals("Tue, 16 Jul 2019 08:29:38 GMT", ResourceLoaderUtils.formatDateHeader(1563265778653L)); }