code: public void sendLoadTrackCommand(int targetPlayer, int rekordboxId,
                                       int sourcePlayer, CdjStatus.TrackSourceSlot sourceSlot, CdjStatus.TrackType sourceType)
              throws IOException {
          final DeviceUpdate update = getLatestStatusFor(targetPlayer);
          if (update == null) {
              throw new IllegalArgumentException("Device " + targetPlayer + " not found on network.");
          }
          sendLoadTrackCommand(update, rekordboxId, sourcePlayer, sourceSlot, sourceType);
      }
docs: Send a packet to the target player telling it to load the specified track from the specified source player.
  
  @param targetPlayer the device number of the player that you want to have load a track
  @param rekordboxId the identifier of a track within the source player's rekordbox database
  @param sourcePlayer the device number of the player from which the track should be loaded
  @param sourceSlot the media slot from which the track should be loaded
  @param sourceType the type of track to be loaded
  
  @throws IOException if there is a problem sending the command
  @throws IllegalStateException if the {@code VirtualCdj} is not active or the target device cannot be found