public static DnsServerAddresses sequential(Iterable<? extends InetSocketAddress> addresses) {
        return sequential0(sanitize(addresses));
    }
@Test
    public void testSequential() {
        DnsServerAddresses seq = DnsServerAddresses.sequential(ADDR1, ADDR2, ADDR3);
        assertThat(seq.stream(), is(not(sameInstance(seq.stream()))));

        for (int j = 0; j < 2; j ++) {
            DnsServerAddressStream i = seq.stream();
            assertNext(i, ADDR1);
            assertNext(i, ADDR2);
            assertNext(i, ADDR3);
            assertNext(i, ADDR1);
            assertNext(i, ADDR2);
            assertNext(i, ADDR3);
        }
    }