@Test
 public void testGetOldestTimestampMultipleEntries() {
   cache.put(status("1", 101));
   cache.put(status("2", 9));
   cache.put(status("3", 13456));
   cache.put(status("4", 8080));
   cache.put(status("5", 11));
   assertEquals(9, cache.getOldestTimestamp());
 }
 @Test
 public void testGetOldestTimestampSingleEntry() {
   cache.put(status("name", 101));
   assertEquals(101, cache.getOldestTimestamp());
 }
 @Test
 public void testGetOldestTimestampEmpty() {
   assertEquals(-1, cache.getOldestTimestamp());
 }