code: public Map<DeckReference, TrackMetadata> getLoadedTracks() {
          ensureRunning();
          // Make a copy so callers get an immutable snapshot of the current state.
          return Collections.unmodifiableMap(new HashMap<DeckReference, TrackMetadata>(hotCache));
      }
docs: Get the metadata of all tracks currently loaded in any player, either on the play deck, or in a hot cue.
  
  @return the track information reported by all current players, including any tracks loaded in their hot cue slots
  
  @throws IllegalStateException if the MetadataFinder is not running