[android]해시 키 구하는 메소드

private void getAppKeyHash() {
        try {
            PackageInfo info = getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_SIGNATURES);
            for (Signature signature : info.signatures) {
                MessageDigest md;
                md = MessageDigest.getInstance("SHA");
                md.update(signature.toByteArray());
                String something = new String(Base64.encode(md.digest(), 0));
                Log.d("Hash key", something);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            Log.e("name not found", e.toString());
        }
}