code: public static boolean isPotentiallyEncryptedString(String string) {
          checkNotNull(string, "string");
  
          // String is base64 encoded
          byte[] encryptedBytes;
          try {
              encryptedBytes = BaseEncoding.base64().omitPadding().decode(string);
          } catch (IllegalArgumentException e) {
              return false;
          }
  
          return isPotentiallyEncryptedBytes(encryptedBytes);
      }
docs: Returns true if the provided String _could_ be encrypted credentials, even if it can't be decrypted
  by a specific instance.