@Test
 public void testIsNumericIPv6IPv4Mapping() {
   assertTrue(LocatorUtils.isNumeric("[::ffff:192.0.2.128]"));
 }
 @Test
 public void testIsNumericHost() {
   assertFalse(LocatorUtils.isNumeric("example.org"));
 }
 @Test
 public void testIsNumericIPv6Loopback() {
   assertTrue(LocatorUtils.isNumeric("[::1]"));
 }
 @Test
 public void testIsNumericIPv6Unspecified() {
   assertTrue(LocatorUtils.isNumeric("[::]"));
 }
 @Test
 public void testIsNumericIPv6GroupedZeroes() {
   assertTrue(LocatorUtils.isNumeric("[2001:db8:85a3::8a2e:370:7334]"));
 }
 @Test
 public void testIsNumericIPv6NoLeadingZeroes() {
   assertTrue(LocatorUtils.isNumeric("[2001:db8:85a3:0:0:8a2e:370:7334]"));
 }
 @Test
 public void testIsNumericIPv6NonReference() {
   // This test distinguishes between an IPv6 address and IPv6 reference.
   assertFalse(LocatorUtils.isNumeric("2001:0db8:85a3:0000:0000:8a2e:0370:7334"));
 }
 @Test
 public void testIsNumericIPv6() {
   assertTrue(LocatorUtils.isNumeric("[2001:0db8:85a3:0000:0000:8a2e:0370:7334]"));
 }
 @Test
 public void testIsNumericIPv4() {
   assertTrue(LocatorUtils.isNumeric("192.168.0.1"));
 }