code: public IOException toUserPresentableException(IOException ioe, String action) throws IOException {
      throw new IOException(toUserPresentableMessage(ioe, action), ioe);
    }
docs: Converts the exception to a user-presentable error message. Specifically,
  extracts message field for HTTP 4xx codes, and creates a generic
  "Internal Server Error" for HTTP 5xx codes.
  
  @param ioe the exception
  @param action the description of the action being performed at the time of error.
  @see #toUserPresentableMessage(IOException, String)