@Override
    public Mapper.Builder parse(String name, Map<String, Object> node, ParserContext parserContext)
        throws MapperParsingException {
      if (parserContext.indexVersionCreated().before(Version.V_1_3_0)) {
        throw new IllegalArgumentException(
            "type="
                + CONTENT_TYPE
                + " is not supported on indices created before version 1.3.0. Is your cluster running multiple datanode versions?");
      }

      FieldNamesFieldMapper.Builder builder = fieldNames();
      if (parserContext.indexVersionCreated().before(Version.V_2_0_0)) {
        parseField(builder, builder.name, node, parserContext);
      }

      for (Iterator<Map.Entry<String, Object>> iterator = node.entrySet().iterator();
          iterator.hasNext(); ) {
        Map.Entry<String, Object> entry = iterator.next();
        String fieldName = Strings.toUnderscoreCase(entry.getKey());
        Object fieldNode = entry.getValue();
        if (fieldName.equals("enabled")) {
          builder.enabled(nodeBooleanValue(fieldNode));
          iterator.remove();
        }
      }
      return builder;
    }