code: public boolean evaluate(final LoggingEvent event, Map matches) {
      if (matches == null) {
        return !(rule.evaluate(event, null));
      }
      Map tempMatches = new HashMap();
      boolean result = !(rule.evaluate(event, tempMatches));
      if (result) {
          for (Iterator iter = tempMatches.entrySet().iterator();iter.hasNext();) {
              Map.Entry entry = (Map.Entry)iter.next();
              Object key = entry.getKey();
              Set value = (Set)entry.getValue();
              Set mainSet = (Set) matches.get(key);
              if (mainSet == null) {
                  mainSet = new HashSet();
                  matches.put(key, mainSet);
              }
              mainSet.addAll(value);
          }
      }
      return result;
    }
docs: {@inheritDoc}