Java tutorial
//package com.java2s; import android.util.Log; import java.net.InetAddress; import java.net.NetworkInterface; import java.net.SocketException; import java.util.Enumeration; public class Main { public static NetworkInterface getActiveNetworkInterface() { Enumeration<NetworkInterface> interfaces = null; try { interfaces = NetworkInterface.getNetworkInterfaces(); } catch (SocketException e) { return null; } while (interfaces.hasMoreElements()) { NetworkInterface iface = interfaces.nextElement(); Enumeration<InetAddress> inetAddresses = iface.getInetAddresses(); /* Check if we have a non-local address. If so, this is the active * interface. * * This isn't a perfect heuristic: I have devices which this will * still detect the wrong interface on, but it will handle the * common cases of wifi-only and Ethernet-only. */ if (iface.getName().startsWith("w")) { //this is a perfect hack for getting wifi alone while (inetAddresses.hasMoreElements()) { InetAddress addr = inetAddresses.nextElement(); if (!(addr.isLoopbackAddress() || addr.isLinkLocalAddress())) { Log.d("LSSDP", "DisplayName" + iface.getDisplayName() + " Name " + iface.getName()); return iface; } } } } return null; } }