code: public boolean evaluate(final LoggingEvent event, Map matches) {
      String eventTimeStampString = RESOLVER.getValue(LoggingEventFieldResolver.TIMESTAMP_FIELD, event).toString();
      long eventTimeStamp = Long.parseLong(eventTimeStampString) / 1000 * 1000;
      boolean result = (eventTimeStamp == timeStamp);
      if (result && matches != null) {
          Set entries = (Set) matches.get(LoggingEventFieldResolver.TIMESTAMP_FIELD);
          if (entries == null) {
              entries = new HashSet();
              matches.put(LoggingEventFieldResolver.TIMESTAMP_FIELD, entries);
          }
          entries.add(eventTimeStampString);
      }
      return result;
    }
docs: {@inheritDoc}