@Test
 public void testGetServiceIdentifierForTcp() throws IOException {
   assertEquals(
       new Name("_sip._tcp.example.org."),
       LocatorUtils.getServiceIdentifier("TCP", new Name("example.org.")));
 }
 @Test
 public void testGetServiceIdentifierForSctpTls() throws IOException {
   assertEquals(
       new Name("_sips._sctp.example.org."),
       LocatorUtils.getServiceIdentifier("TLS-SCTP", new Name("example.org.")));
 }
 @Test(expected = IllegalArgumentException.class)
 public void testGetServiceIdentifierForInvalidTransport() throws IOException {
   LocatorUtils.getServiceIdentifier("FOO", new Name("example.org."));
 }