code: public static <T extends Serializable> String serialize(T obj) throws IOException {
      return serialize(obj, DEFAULT_ENCODING);
    }
docs: Serialize an object into a String. The object is first serialized into a byte array,
  which is converted into a String using {@link BaseEncoding#base64()}.
  
  @param obj A {@link Serializable} object
  @return A String representing the input object
  @throws IOException if it fails to serialize the object