KeyHash.java

public class KeyHash {
    public static void generateKeyHash(Context context) {
        try {
            PackageInfo info = context.getPackageManager().getPackageInfo(context.getPackageName(), PackageManager.GET_SIGNATURES);
            for (Signature signature : info.signatures) {
                MessageDigest md = MessageDigest.getInstance("SHA");
                md.update(signature.toByteArray());

                String something = new String(Base64.encode(md.digest(), 0));
                Log.e("Hash key", something);
            }
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
    }
}