I have been using NetworkInterface.getNetworkInterfaces()
to query the Network Interfaces on my machine. Essentially I am trying to find Network Interface Cards. These are usually called something like eth0, eth1 etc..
Its been working great on win xp and even vista with a litle filtering.
I just noticed in certain configurations of windows 7 I get a large number of listed network adapters. Way more than on xp and vista. I have only one card configured but seem to get three different network interfaces
- Intel(R) 82567LM-3 Gigabit Network Connection
- Intel(R) 82567LM-3 Gigabit Network Connection-QoS Packet Scheduler-0000
- Intel(R) 82567LM-3 Gigabit Network Connection-WFP LightWeight Filter-0000
Why 3 different points for essentially the same thing.
I also have six entries for something called WAN MINIPORT. (See below for output)
I can filter out these but of course there is a performance cost in going through so much crap. Does anyone know why these entries are created and how to minimise them ?
As an example on my system I wrote code like this
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.Arrays;
import java.util.Collections;
import java.util.Enumeration;
import static java.lang.System.out;
public class ListNetsEx {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Enumeration<NetworkInterface> nets;
try {
nets = NetworkInterface.getNetworkInterfaces();
for (NetworkInterface netint : Collections.list(nets))
displayInterfaceInformation(netint);
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private static void displayInterfaceInformation(NetworkInterface netint) throws SocketException {
// TODO Auto-generated method stub
out.printf("Display name: %s\n", netint.getDisplayName());
out.printf("Name: %s\n", netint.getName());
Enumeration<InetAddress> inetAddresses = netint.getInetAddresses();
for (InetAddress inetAddress : Collections.list(inetAddresses)) {
out.printf("InetAddress: %s\n", inetAddress);
}
out.printf("Up? %s\n", netint.isUp());
out.printf("Loopback? %s\n", netint.isLoopback());
out.printf("PointToPoint? %s\n", netint.isPointToPoint());
out.printf("Supports multicast? %s\n", netint.supportsMulticast());
out.printf("Virtual? %s\n", netint.isVirtual());
out.printf("Hardware address: %s\n",
Arrays.toString(netint.getHardwareAddress()));
out.printf("MTU: %s\n", netint.getMTU());
out.printf("\n");
}
}
On windows 7 output is
Display name: Software Loopback Interface 1 Name: lo InetAddress: /0:0:0:0:0:0:0:1 InetAddress: /127.0.0.1 Up? true Loopback? true PointToPoint? false Supports multicast? true Virtual? false Hardware address: [] MTU: -1 Display name: WAN Miniport (SSTP) Name: net0 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (IKEv2) Name: net1 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (L2TP) Name: net2 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (PPTP) Name: net3 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (PPPOE) Name: ppp0 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (IPv6) Name: eth0 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (Network Monitor) Name: eth1 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (IP) Name: eth2 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: RAS Async Adapter Name: ppp1 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: Intel(R) 82567LM-3 Gigabit Network Connection Name: eth3 InetAddress: /fe80:0:0:0:b1b1:7531:17b1:bf26%11 InetAddress: /172.24.9.148 Up? true Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: [120, 43, -53, 125, -80, 74] MTU: 1500 Display name: Microsoft ISATAP Adapter Name: net4 Up? false Loopback? false PointToPoint? true Supports multicast? false Virtual? false Hardware address: [0, 0, 0, 0, 0, 0, 0, -32] MTU: 1280 Display name: Teredo Tunneling Pseudo-Interface Name: net5 InetAddress: /fe80:0:0:0:e0:0:0:0%13 Up? false Loopback? false PointToPoint? true Supports multicast? false Virtual? false Hardware address: [0, 0, 0, 0, 0, 0, 0, -32] MTU: 1280 Display name: Microsoft ISATAP Adapter #2 Name: net6 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: Intel(R) 82567LM-3 Gigabit Network Connection-QoS Packet Scheduler-0000 Name: eth4 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: Intel(R) 82567LM-3 Gigabit Network Connection-WFP LightWeight Filter-0000 Name: eth5 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (Network Monitor)-QoS Packet Scheduler-0000 Name: eth6 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (IP)-QoS Packet Scheduler-0000 Name: eth7 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1 Display name: WAN Miniport (IPv6)-QoS Packet Scheduler-0000 Name: eth8 Up? false Loopback? false PointToPoint? false Supports multicast? true Virtual? false Hardware address: null MTU: -1
Windows defines many interfaces for internal use. Java just returns what the OS tell gives it, none of these are added by Java.
You should be able to find entries for all these devices in the Windows Registry.
来源：https://stackoverflow.com/questions/5953460/can-anyone-explain-why-java-getnetworkinterfaces-returns-so-many-interfaces-on-w