code: private KeyFinder<S4Event> getKeyFinder() {
  		KeyFinder<S4Event> keyFinder = new KeyFinder<S4Event>() {
  			@Override
  			public List<String> get(S4Event s4event) {
  				List<String> results = new ArrayList<String>();
  				results.add(s4event.getKey());
  				return results;
  			}
  		};
  
  		return keyFinder;
  	}
docs: KeyFinder sets the keys for a specific event.
  
  @return KeyFinder