WifiManager wm = (WifiManager)ctx.getSystemService(Context.WIFI_SERVICE);
String macAddress = wm.getConnectionInfo().getMacAddress();
it is a String in hex format, for example:
"00:23:76:B7:2B:4D"
I want to convert this string into a byte array so that I can use MessageDigest sha1 on it
I got it worked in Python by using the excaping \x instead of : using the hashlib module.
But I would I do it in android/java? Thanks!
This code:
Byte.parseByte(mac[i], 16);
Not parse correctly hexadecimals numbers started with letters: "AE", "EF", etc...
Revised code:
WifiManager wm = (WifiManager) ctx.getSystemService(Context.WIFI_SERVICE);
if (wm != null) {
String[] mac = wm.getConnectionInfo().getMacAddress().split(":");
byte[] macAddress = new byte[6]; // mac.length == 6 bytes
for(int i = 0; i < mac.length; i++) {
macAddress[i] = Integer.decode("0x" + mac[i]).byteValue();
}
}
WifiManager wm = (WifiManager)ctx.getSystemService(Context.WIFI_SERVICE);
byte[] macAddress = wm.getConnectionInfo().getMacAddress().getBytes();
Revised Solution:
WifiManager wm = (WifiManager)ctx.getSystemService(Context.WIFI_SERVICE);
String[] mac = wm.getConnectionInfo().getMacAddress().split(":");
byte[] macAddress = new byte[6];
for(int i = 0; i < mac.length; i++) {
macAddress[i] = Byte.parseByte(mac[i], 16);
}
getBytes will return the 34 Unicode code points rather than the 6 bytes of the MAC address.By this you get mac address in byte array so you no need to convert it.
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
public class App{
public static void main(String[] args){
InetAddress ip;
try {
ip = InetAddress.getLocalHost();
System.out.println("Current IP address : " + ip.getHostAddress());
NetworkInterface network = NetworkInterface.getByInetAddress(ip);
byte[] mac = network.getHardwareAddress();
System.out.print("Current MAC address : ");
StringBuilder sb = new StringBuilder();
for (int i = 0; i < mac.length; i++) {
sb.append(String.format("%02X%s", mac[i], (i < mac.length - 1) ? "-" : ""));
}
System.out.println(sb.toString());
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (SocketException e){
e.printStackTrace();
}
}
}
/Copy from here : copy from http://www.mkyong.com/java/how-to-get-mac-address-in-java/comment-page-1/#comment-139182/
In android API level 28, there is an easier way of doing this: https://developer.android.com/reference/android/net/MacAddress.
android.net.MacAddress.fromString(s).toByteArray();
