code: public String writeToString() throws IOException {
          final Reader reader = getReader();
          try {
              return CharStreams.toString(reader);
          } finally {
              reader.close();
          }
      }
docs: Writes all the character data of this representation to a {@code String} object. Conversion
  from byte to character data, if required, is performed according to the charset specified
  by the MIME type metadata property ({@link NIE#MIME_TYPE}). If some data has been already
  read via {@code getInputStream()} or {@code getReaer()}, it will not be returned in the
  result.
  
  @return a {@code String} containg the full character-based content of this representation
  @throws IOException
  in case access to binary data fails