Android网络类型判断(2g、3g、wifi)

private String getPhoneIp() {
        try {  
            for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {  
                NetworkInterface intf = en.nextElement();  
                for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {  
                    InetAddress inetAddress = enumIpAddr.nextElement();  
                    if (!inetAddress.isLoopbackAddress() && inetAddress instanceof Inet4Address) {  
                    //if (!inetAddress.isLoopbackAddress() && inetAddress instanceof Inet6Address) {  
                        return inetAddress.getHostAddress().toString();  
                    }  
                }  
            }  
        } catch (Exception e) {  
        }  
        return ""; 
    }