@Test
 public void getServerNameViaHostHeaderAsIpv6AddressWithPort() {
   String ipv6Address = "[2001:db8:0:1]:8081";
   request.addHeader(HOST, ipv6Address);
   assertEquals("2001:db8:0:1", request.getServerName());
 }
 @Test
 public void getServerNameWithCustomName() {
   request.setServerName("example.com");
   assertEquals("example.com", request.getServerName());
 }
 @Test
 public void getServerNameViaHostHeaderWithPort() {
   String testServer = "test.server";
   request.addHeader(HOST, testServer + ":8080");
   assertEquals(testServer, request.getServerName());
 }
 @Test
 public void getServerNameWithDefaultName() {
   assertEquals("localhost", request.getServerName());
 }