获取安卓的SH1安全码

 用于获取手机联系人 信息

public static String sHA1(Context context) {
    try {
        PackageInfo info = context.getPackageManager().getPackageInfo(
                context.getPackageName(), PackageManager.GET_SIGNATURES);
        byte[] cert = info.signatures[0].toByteArray();
        MessageDigest md = MessageDigest.getInstance("SHA1");
        byte[] publicKey = md.digest(cert);
        StringBuffer hexString = new StringBuffer();
        for (int i = 0; i < publicKey.length; i++) {
            String appendString = Integer.toHexString(0xFF & publicKey[i])
                    .toUpperCase(Locale.US);
            if (appendString.length() == 1)
                hexString.append("0");
            hexString.append(appendString);
        }
        return hexString.toString();
    } catch (PackageManager.NameNotFoundException e) {
        e.printStackTrace();
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    }
    return null;
}