func (f *FakeNetwork) AddInterfaceAddr(intf *net.Interface, addrs []net.Addr) {
	f.NetworkInterfaces = append(f.NetworkInterfaces, *intf)
	f.Address[intf.Name] = addrs
}

// InterfaceAddrs is part of NetworkInterfacer interface.
func (f *FakeNetwork) InterfaceAddrs() ([]net.Addr, error) {
	addrs := make([]net.Addr, 0)
	for _, value := range f.Address {

#  IP_ALIAS_SUBNETWORK
function detect-k8s-subnetwork() {
  local subnetwork_url
  subnetwork_url=$(gcloud compute instances describe \
    "${KUBE_MASTER}" --project="${PROJECT}" --zone="${ZONE}" \
    --format='value(networkInterfaces[0].subnetwork)')
  if [[ -n ${subnetwork_url} ]]; then
    IP_ALIAS_SUBNETWORK=${subnetwork_url##*/}
  fi
}

# Set IP_ALIAS_SUBNETWORK's allowSubnetCidrRoutesOverlap to a boolean value.

  local ip="${3}"

  local aliases
  aliases=$(gcloud compute instances describe "${name}" --project "${PROJECT}" --zone "${zone}" --flatten='networkInterfaces[0].aliasIpRanges[]' --format='value[separator=':'](networkInterfaces[0].aliasIpRanges.subnetworkRangeName,networkInterfaces[0].aliasIpRanges.ipCidrRange)' | sed 's/^://' | paste -s -d';' -)
  aliases="${aliases:+${aliases};}${ip}/32"

// for testing purposes.
type networkInterfacer interface {
	InterfaceByName(intfName string) (*net.Interface, error)
	Addrs(intf *net.Interface) ([]net.Addr, error)
	Interfaces() ([]net.Interface, error)
}

// networkInterface implements the networkInterfacer interface for production code, just
// wrapping the underlying net library function calls.
type networkInterface struct{}

        Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
        if (interfaces != null) {
            while (interfaces.hasMoreElements()) {
                analyzeNetworkInterface(interfaces.nextElement());
            }
        }
    }

    private void analyzeNetworkInterface(NetworkInterface networkInterface) {

*/

package util

import (
	"net"
)

// NetworkInterfacer defines an interface for several net library functions. Production
// code will forward to net library functions, and unit tests will override the methods
// for testing purposes.
type NetworkInterfacer interface {
	InterfaceAddrs() ([]net.Addr, error)
}

// RealNetwork implements the NetworkInterfacer interface for production code, just

	return npa.matchAll
}

// GetNodeIPs return all matched node IP addresses for npa's CIDRs. If no matching
// IPs are found, it returns an empty list.
// NetworkInterfacer is injected for test purpose.
func (npa *NodePortAddresses) GetNodeIPs(nw NetworkInterfacer) ([]net.IP, error) {
	addrs, err := nw.InterfaceAddrs()
	if err != nil {
		return nil, fmt.Errorf("error listing all interfaceAddrs from host, error: %v", err)
	}

    ImmutableSet.Builder<String> builder = ImmutableSet.builder();
    Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
    assertTrue(interfaces.hasMoreElements());
    while (interfaces.hasMoreElements()) {
      NetworkInterface i = interfaces.nextElement();
      builder.add(i.getName()).add(String.valueOf(i.getIndex()));
    }
    return builder.build();

		if !ip.Equal(tc.expected) {
			t.Errorf("case[%v]: expected %v, got %v .err : %v", tc.tcase, tc.expected, ip, err)
		}
	}
}

func TestAddrs(t *testing.T) {
	var nw networkInterfacer = validNetworkInterface{}
	intf := net.Interface{Index: 0, MTU: 0, Name: "eth3", HardwareAddr: nil, Flags: 0}
	addrs, err := nw.Addrs(&intf)
	if err != nil {
		t.Errorf("expected no error got : %v", err)
	}

    private static final String nonLoopbackAddress() {
        println("Looking at network interfaces")
        def address = Collections.list(NetworkInterface.getNetworkInterfaces())
            .collectMany { it.isLoopback() ? [] : Collections.list(it.inetAddresses) }
            .find { it instanceof Inet4Address && !it.isLoopbackAddress() }
            ?.hostAddress