Opening an adapter and capturing the packets

Obtain a packet capture handle (Pcap) with a specific network interface (adapter) to look at packets on the network and process it with Pcap.loop(int, PacketHandler, T args).

Once the adapter is opened, the capture can be started with Pcap.dispatch(int, PacketHandler, T args) or Pcap.dispatch(int, PacketHandler, T args). These two functions are very similar, the difference is that Pcap.dispatch(int, PacketHandler, T args) returns (although not guaranteed) when the timeout expires while Pcap.loop(int, PacketHandler, T args) doesn't return until maximum packets have been captured, so it can block for an arbitrary period on an under-utilized network.

Docs: libpcap, javadoc.

public static void main(String[] _args)
    throws ErrorException, PermissionDeniedException, PromiscuousModePermissionDeniedException,
        TimestampPrecisionNotSupportedException, RadioFrequencyModeNotSupportedException,
        NoSuchDeviceException, ActivatedException, InterfaceNotUpException,
        InterfaceNotSupportTimestampTypeException {
  var service = Service.Creator.create("PcapService");
  try (var pcap =, new DefaultLiveOptions())) {
    try {
          (args, header, buffer) -> {
            System.out.println("Args     : " + args);
            System.out.println("Header   : " + header);
            System.out.println("Packet   : " + buffer);
          "Hello pcap!");
    } catch (BreakException e) {
    } catch (ErrorException e) {

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