this.scrollSize = scrollSize;
    }

    protected static class EsTimestampConverter implements Converter {
        public static final DateTimeFormatter DEFAULT_DATE_PRINTER = ISODateTimeFormat.dateTime().withZone(DateTimeZone.UTC);

        @Override
        public String getAsString(final Object value) {
            if (value instanceof Date) {
                return DEFAULT_DATE_PRINTER.print(((Date) value).getTime());