DnsAddressStreamList Class — netty Architecture

Source Code

resolver-dns/src/main/java/io/netty/resolver/dns/DnsResolveContext.java lines 739–791

    private static final class DnsAddressStreamList extends AbstractList<InetSocketAddress> {

        private final DnsServerAddressStream duplicate;
        private List<InetSocketAddress> addresses;

        DnsAddressStreamList(DnsServerAddressStream stream) {
            duplicate = stream.duplicate();
        }

        @Override
        public InetSocketAddress get(int index) {
            if (addresses == null) {
                DnsServerAddressStream stream = duplicate.duplicate();
                addresses = new ArrayList<InetSocketAddress>(size());
                for (int i = 0; i < stream.size(); i++) {
                    addresses.add(stream.next());
                }
            }
            return addresses.get(index);
        }

        @Override
        public int size() {
            return duplicate.size();
        }

        @Override
        public Iterator<InetSocketAddress> iterator() {
            return new Iterator<InetSocketAddress>() {
                private final DnsServerAddressStream stream = duplicate.duplicate();
                private int i;

                @Override
                public boolean hasNext() {
                    return i < stream.size();
                }

                @Override
                public InetSocketAddress next() {
                    if (!hasNext()) {
                        throw new NoSuchElementException();
                    }
                    i++;
                    return stream.next();
                }

                @Override
                public void remove() {
                    throw new UnsupportedOperationException();
                }
            };
        }
    }