Get Facebook key hash using Android code

GetFacebookKeyHash.java

try {
    PackageInfo info = getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_SIGNATURES);
    for (Signature signature : info.signatures) {
        MessageDigest md = MessageDigest.getInstance("SHA");
        md.update(signature.toByteArray());
        Log.d("KeyHash: ", Base64.encodeToString(md.digest(), Base64.DEFAULT));
    }
} catch (NameNotFoundException e) {
    e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
    e.printStackTrace();
}